Item 1 :

https://backpack.tf/item/15507325002

Trade 4 :

https://backpack.tf/profiles/76561198083621911#!/compare/1743897600/1743984000

https://backpack.tf/profiles/76561198075499550#!/compare/1743552000/1743984000

pure 13 keys for the hat and 21 ref for change, it may be a quicksell tho

my Item :

https://backpack.tf/item/15228053567

trade 1 :

https://backpack.tf/profiles/76561199564942025#!/compare/1746316800/1746403200

https://backpack.tf/profiles/76561198313907641#!/compare/1746144000/1746403200

13 keys for the unu and 25 ref for change

this was a quickbuy from a bot tho

https://backpack.tf/profiles/76561199564942025#!/compare/1746316800/1746403200

https://backpack.tf/profiles/76561198313907641#!/compare/1746144000/1746403200

https://backpack.tf/profiles/76561198083621911#!/compare/1743379200/1743465600 - Bulk

https://backpack.tf/profiles/76561198075499550#!/compare/1743984000/1744070400 - Quicksold for 13 Keys, probably with the 35 Refined as change

https://backpack.tf/profiles/76561198012514588#!/compare/1743984000/1744070400 - Quicksold for 12 Keys + 34 Refined

https://backpack.tf/profiles/76561198349848918#!/compare/1742428800/1742515200 - 14 Keys

https://backpack.tf/profiles/76561197975587947#!/compare/1743638400/1743724800 - 21 Keys, but this is a high outlier because...

https://backpack.tf/profiles/76561198382237103#!/compare/1745884800/1746144000 - It was later dumped to quicksell.store who listed it for 18.43

https://backpack.tf/profiles/76561198355443649#!/compare/1743984000/1744243200 - Probably gambled

https://backpack.tf/profiles/76561199110412711#!/compare/1742601600/1742774400 - ?

https://backpack.tf/profiles/76561198049501416#!/compare/1743120000/1743465600 - ?

https://backpack.tf/profiles/76561199104559253#!/compare/1741910400/1742083200 - 14 Keys

https://backpack.tf/profiles/76561199581722058#!/compare/1745798400/1745884800 - 13 Keys + 0.44 Refined

https://backpack.tf/profiles/76561199551005632#!/compare/1746662400/1746748800 - 15 Keys + 30 Refined

A range of 13 - 15 here would work.

massive thanks to https://backpack.tf/u/76561198085880346 for helping me here