1 of 3 in existence, only 4 sales found, here you go!

Item: https://backpack.tf/item/9430864724

Sale #1

It all started from here :3

https://backpack.tf/profiles/76561198083134207#!/compare/1603324800/1603411200

https://backpack.tf/profiles/76561198124398703#!/compare/1603238400/1603411200

Sold for 55 Keys

Sale #2

https://backpack.tf/profiles/76561198124398703#!/compare/1603497600/1603756800

https://backpack.tf/profiles/76561198331167728#!/compare/1603584000/1603670400

Sold for 45 Keys

Sale #3

https://backpack.tf/profiles/76561198331167728#!/compare/1603670400/1603756800

https://backpack.tf/profiles/76561198179712943#!/compare/1603670400/1603756800

Sold for 48 Keys

Sale #4

https://backpack.tf/profiles/76561198179712943#!/compare/1604102400/1604275200

https://backpack.tf/profiles/76561198322957656#!/compare/1604188800/1604275200

https://backpack.tf/profiles/76561198322957656#!/compare/1604275200/1604361600

Sold this unusual + 4 Keys for Plum Prankster Burning Question(48 + 4 Keys = 52 Keys) [can use there as a price]

No marketplace sales

Summary

Sales at

45 Keys

48 Keys

55 Keys

Conclusion

I'd suggest a price for 48 keys flat as the buyer for 55 keys, resold for 45 keys immediately. Thanks for a quick tip with the suggestion Dante and Strange.