Only 1 valid sale found:

Marketplace.tf - https://marketplace.tf/items/tf2/313;5;u36

$14.49 / $1.98 (https://manic.tf/keyprice/?at=2020-07-07) = 7.32 ~ 7.5 keys

unknown b/o and item history.

untraced sales and sales from ScrapTF: https://backpack.tf/item/845175347

Current listings: https://gyazo.com/105c79ca0893a7e036e5e7a30c938361

No seller, only buying highest at 6.02 keys.

2 sellers at marketplace.tf, both selling at $15.99 / ~$1.87 = 8.55 keys

Seller 1: https://backpack.tf/item/2598677984 (might have been there for 7 months)

Seller 2: https://backpack.tf/item/712588038 (unknown, the other sales in here also untraceable)