Whoa, two here.

Sold for 31 keys

https://backpack.tf/profiles/76561198061302796#!/compare/1589328000/1589760000

https://backpack.tf/profiles/76561198070705963#!/compare/1589328000/1589414400

Sold for Strange Killstreak Australium Sniper Rifle (26.88 keys)+ The Big Kill (8.1 keys)+ Strange Australium Axtinguisher (5.325 keys)

https://backpack.tf/profiles/76561198148511293#!/compare/1588464000/1588550400

https://backpack.tf/profiles/76561198061302796#!/compare/1587686400/1588550400

26.88 + 8.1 + 5.325 = 40.305 rounding to 40 keys

Sniper Rifle Classifieds:

https://gyazo.com/03c505e6cb97ff8cb36f7bfdc13946cf

Using SCM of 26.88 keys

Classifieds:

https://gyazo.com/0e92b85571d8b4995bb0ebed73bc3d9b

Sales are at 31 and 40. Buyers are at 30. Since 31 is very close, excluding 31. Taking 40 keys here.