ORCHARD PARK, N.Y. -- The Buffalo Bills have been one of the NFL's biggest surprises halfway through the 2019 NFL season, sporting the AFC's second-best record at 5-1.

They're one of three teams allowing fewer than 300 yards per game and rank third in points allowed per game, but there's room to improve on the other side of the ball. Buffalo owns the NFL's seventh-best rushing attack (135.8 yards per game), but ranks 21st or worse in passing yards per game, completion percentage, yards per attempt and passer rating through six games.

To alleviate the pressure on the running game, trading for another receiver before the Oct. 29 trade deadline could make sense.

"The Bills have put themselves in a good position to play meaningful games the rest of the season," said ESPN analyst Mike Tannenbaum, a former Jets and Dolphins personnel executive. "Getting a frontline receiver would only enhance their offense and take some of the pressure off their running back, and make players like Devin Singletary and Frank Gore more dangerous."

Buffalo has some weapons, starting with John Brown, who is playing like a legitimate No. 1 receiver. His 473 receiving yards rank 12th among wide receivers this season and he is on pace for 88 receptions, 1,261 yards and five touchdowns, which would be the best season of his career. Only four receivers last season finished with as many yards on fewer catches: Mike Evans, Tyreek Hill, T.Y. Hilton and Robert Woods.

Like Brown, Cole Beasley signed with the Bills this offseason and has largely done what he was brought in to do; in fact, the 80-catch, 755-yard season he's on pace for would be the second-best of his career. However, it's the unproven depth behind those two -- no other Bills receiver has more than seven receptions -- that Buffalo could feel an urgency to address with another veteran who improves quarterback Josh Allen's options.

While a trade makes sense on paper, the Bills don't necessarily need to pursue a deal for a perceived superstar. Especially given the price teams have paid this season for top-tier players.

"What the market has told us is that for teams that are looking to acquire players -- be it [offensive tackle] Laremy Tunsil or [cornerback] Jalen Ramsey -- there's significant premiums in the marketplace," Tannenbaum said.

The Texans gave the Dolphins two first-round picks and a second-round pick in part of the exchange for Tunsil and receiver Kenny Stills, and the Rams dealt two first-round picks to the Jaguars for Ramsey last week.

Two receivers often mentioned in trade rumors this season -- Minnesota Vikings' Stefon Diggs and Cincinnati Bengals' A.J. Green -- could command a comparable price to the Tunsil and Ramsey trades.

Diggs is in the first year of a five-year, $72 million extension with the Vikings, which guarantees him $40 million. He's also in his prime at 25 years old and finished each of his first four seasons with at least 52 catches, 720 yards and three scores. For his talents, Diggs might be underused in an offense built around the run, but the threat he offers as a vertical and play-action threat alongside Adam Thielen gives the Vikings the best receiver duo in football.

Few players in the league are truly untouchable, but Minnesota (5-2) has little incentive to trade him for anything less than a "Godfather"-type offer, and a league source said the Vikings are not interested in trading Diggs. And Buffalo, which has shied away from knee-jerk, win-now decisions during general manager Brandon Beane and coach Sean McDermott's three seasons at the helm, would be making an out-of-character move by parting with multiple early-round picks for Diggs -- who would be joining a team that runs the ball nearly as much as the Vikings.

Green, who injured his ankle on the first day of training camp, is not expected to play until after Oct. 29, per ESPN's Adam Schefter. He's also in the final year of his contract and, including this season, has missed 14 games over the past two seasons. Spotrac.com estimates his market value at three-years, $50 million for his next contract, which the Bills could afford given their estimated $89 million of salary-cap space this coming offseason.

He is a Bengals icon, which could make trading him unpopular with their fans, but his injury history and the team's rebuilding effort make him a candidate.

ESPN's Bill Barnwell proposed a trade for Green that involved the Bengals sending him and a 2020 second-round pick to the 49ers for a 2020 first-round pick and a 2021 second-round pick. That kind of price still seems out of character for the Bills, who gave up third-round and seventh-round picks to acquire what they felt was a No. 1 receiver (Kelvin Benjamin) in 2017.

A more realistic trade target for the Bills is Denver Broncos veteran Emmanuel Sanders. He's spent much of his career as an effective No. 2 option, with 7,391 receiving yards and 39 touchdowns on 565 catches. After tearing his Achilles tendon in December, Sanders, 32, has played all seven games this season for the fading Broncos, reeling in 30 passes for 367 yards and two scores.

Barnwell proposed the Patriots parting ways with a 2020 sixth-round pick for Sanders; Buffalo could do better and package any of its four fifth-round picks in 2020 and 2021, or its three sixth-round picks in 2020. Beane accumulated a bevy of late-round picks over the past few months, in part to open up the possibility of flipping them for an impactful starter -- regardless of position. A player such as Sanders, who would complement an already-effective Brown and Beasley, fits that narrative.

The Bills do have young receivers Isaiah McKenzie, Robert Foster and Duke Williams who have all flashed brilliance in their brief careers. But if Buffalo is to attack its window of opportunity during a down year in the AFC, trading for a starting-caliber receiver could be the move to help solidify its place among the conference's elite teams.