Using last 2 months.

Sale 1:

Sold for 37 keys

Seller: https://backpack.tf/profiles/76561197982879578#!/compare/1536105600/1536278400

Buyer: https://backpack.tf/profiles/76561198029668965#!/compare/1536192000/1536278400

https://backpack.tf/item/4959823610

X = 37

Sale 2:

Sold for $23 on marketplace

https://marketplace.tf/items/1106;5;u3016

Gonna be way too low.

Other Sales:

https://backpack.tf/item/2778126793 (#1)

https://backpack.tf/item/4959823610 (#2 & #3)

#1

Bulk for Burning Tundra Top

https://backpack.tf/profiles/76561198130948401#!/compare/1537315200/1537401600

https://backpack.tf/profiles/76561198050930436#!/compare/1537315200/1537401600

#2

Bulk?

https://backpack.tf/profiles/76561198043903498#!/compare/1535932800/1536019200

https://backpack.tf/profiles/76561197982879578#!/compare/1535846400/1536019200

#3

Probably dumped on scrap

https://backpack.tf/profiles/76561198029668965#!/compare/1537401600/1537574400

https://backpack.tf/profiles/76561198289262378#!/compare/1537228800/1537401600

Sellers:

https://i.imgur.com/Eyb5zok.png

https://backpack.tf/item/3534812054 - 39 keys (also listed for $60 on marketplace, which is currently ~34 keys)

https://backpack.tf/item/2988156430 - 40 keys

https://backpack.tf/item/4959823610 - 40 keys

Sales at:

37

Can’t tell how long it has been listed for on marketplace, so I won’t use that as the low-end. Screenshot shows that it was not listed around 11 days ago: https://i.imgur.com/XQ4EPy0.png

The $60 seller on marketplace may have been the one that bought it for $23, which means it would’ve been there for only a day.

Going with 37 flat.