Item history - https://backpack.tf/item/2241483629

Sale 1

https://backpack.tf/profiles/76561198072098273#!/compare/1614902400/1614988800

https://backpack.tf/profiles/76561198105071091#!/compare/1614902400/1614988800

Bulky

Sale 2

https://backpack.tf/profiles/76561198105071091#!/compare/1616544000/1616889600

https://backpack.tf/profiles/76561198062017881#!/compare/1616889600/1616976000

Sold for 37 keys

Sale 3

https://backpack.tf/profiles/76561198062017881#!/compare/1617667200/1617840000

https://backpack.tf/profiles/76561198114402400#!/compare/1617753600/1617840000

Bulk for Strange Chiroptera Venenata Private Eye

Sale 4

https://backpack.tf/profiles/76561198114402400#!/compare/1619222400/1619308800

https://backpack.tf/profiles/76561198035547951#!/compare/1619222400/1619308800

Sold for:

Vivid Plasma Hat of Cards - https://gladiator.tf/listings/6085c942529582d984efa380 - 25 key buyers

Purple Confetti Broadband Bonnet - https://gladiator.tf/listings/6085b2a6531f17d8f8880513 - 6 key buyers

5 keys

25 + 6 + 5 = 36 keys

https://gladiator.tf/listings/60858bab261696c547d04af1 - 40 key buyout

This would obviously cap at 40 keys

Sales

37, 40 and 40 pure, the one you provided.

Resuggest at 37 - 40 keys here

Pastebin of above work:

https://pastebin.com/iGcGe0Pc

please re-suggest at 37 - 40 keys given the additional information provided by aj