Sale 1:

Sold for 14 keys

Seller: https://backpack.tf/profiles/76561198344933095#!/compare/1522800000/1522886400

Buyer: https://backpack.tf/profiles/76561198056531196#!/compare/1522800000/1522886400

Bot.tf confirms: https://i.imgur.com/310IptW.png

X = 14

Sale 2:

Sold for $18.1 on Marketplace.tf

https://marketplace.tf/items/1116;5;u3012

Can’t find item history, probably sold too quick anyways.

18.1/1.97 = ~9.19

X = 9

Sellers:

~19.7 keys:

https://i.imgur.com/gcBxO30.png

https://backpack.tf/item/3121898878

20 keys:

https://i.imgur.com/Mhu4Uh5.png

https://backpack.tf/item/2820645562

And another on Marketplace.tf for ~15 keys worth:

https://marketplace.tf/items/1116;5;u3012

https://backpack.tf/item/3211070477

Would make sense if this was the one that was bought for $18.1 on mp.tf

Sales at:

9

14

Buyer at 9 keys: https://i.imgur.com/11b4W6g.png

Excluding 9.

Going with 14 flat.