Resuggestion. Danke, Xergoyf

Green Energy Spiky Viking

https://backpack.tf/item/8782687787

https://backpack.tf/profiles/76561198210395733#!/compare/1590710400/1591056000

https://backpack.tf/profiles/76561198016706143#!/compare/1590883200/1591056000

Untrace. Could be Max's Head

Xergoyf:

Sale 1 looks like 16 keys from the buyers side https://backpack.tf/profiles/76561198016706143#!/compare/1590883200/1591056000

Judging by the histories, it looks like the 16 pure was instantly spent towards purchasing the Max Head.

Taking 16 keys

https://backpack.tf/profiles/76561198016706143#!/compare/1592352000/1592438400

https://backpack.tf/profiles/76561198053809624#!/compare/1592611200/1593043200

Untrace

https://backpack.tf/profiles/76561198053809624#!/compare/1593388800/1593475200

https://backpack.tf/profiles/76561198359746121#!/compare/1593388800/1593475200

Sold for Cloud 9 Aviator Assassin(15.5) + 4 TOD Tickets + ~ 15 ref of stuff

Taking 2 TOD as 1 key.

Total = 15.5 + 2 keys + 15 ref = 18 keys

https://backpack.tf/profiles/76561198359746121#!/compare/1597536000/1597622400

https://backpack.tf/profiles/76561198299678312#!/compare/1591056000/1597622400

Bulk

Marketplace sale: https://marketplace.tf/items/tf2/31100;5;u9

Sold for $39.99 / $1.79 = 22.34 keys ~ 22 keys

Sales at 19 and 22. Even if considering that the Max's Head was indeed in the sale, this will still be in range.

Pricing this at 16 - 22.