Sale 1:

Sold for 4 keys + 12.77 ref (rounds to 4 keys)

https://backpack.tf/profiles/76561198311498888#!/compare/1753228800/1753315200

https://backpack.tf/profiles/76561198834256329#!/compare/1753228800/1753315200

https://backpack.tf/item/12571668792

= 4 keys

Sale 2:

Sold to STN for 3 keys + 16 ref (rounds to 3.5 keys)

https://backpack.tf/profiles/76561198089021697#!/compare/1747872000/1756166400

https://backpack.tf/profiles/76561199581722058#!/compare/1753833600/1753920000

https://backpack.tf/item/12408595044

= 3.5 keys

Marketplace Sales:

https://marketplace.tf/items/tf2/31320;5;u3115

https://backpack.tf/item/13432484046

$13, August 23rd

https://marketplace.tf/items/tf2/5021;6 - keys were $1.84

13/1.84 = 7.065, rounds to 7 keys

Other Sales:

#1

https://backpack.tf/profiles/76561199581722058#!/compare/1754006400/1754092800

https://backpack.tf/profiles/76561199454798964#!/compare/1754006400/1754352000

https://backpack.tf/item/12408595044

Untraceable

#2

https://backpack.tf/profiles/76561199454798964#!/compare/1754352000/1754870400

https://backpack.tf/profiles/76561199026390261#!/compare/1754784000/1754870400

https://backpack.tf/item/12408595044

Untraceable

https://backpack.tf/item/12416851784 - mannco

Sellers:

https://marketplace.tf/items/tf2/31320;5;u3115

https://backpack.tf/item/12790825843 - $13 (~7 keys)

https://backpack.tf/item/12838840453 - $13

https://backpack.tf/item/12588977007 - $13

Sales at:

3.5

4

7 (marketplace)

https://i.imgur.com/TUOQBHT.png - Buyers at ~3.7, excluding 3.5.

Taking 4-7 keys.