more recent sales here too

https://marketplace.tf/items/tf2/30810;5;u107;strange

Those Marketplace sales come out to be 29 Keys, 30 Keys, and 26 Keys. 37 is probably the higher outlier here.

The Shotgun Kit is ~1 Key, so your sale is 38 Keys.

https://marketplace.tf/items/tf2/30810;5;u107;strange - More sales at $69.69 (37 Keys) and $79.69 (42 Keys)

https://backpack.tf/profiles/76561198057984275#!/compare/1586649600/1586736000 - Sold for a Strange Ghosts Nickel + 4 Keys (use there)

https://backpack.tf/profiles/76561198095022965#!/compare/1587081600/1587168000 - Sold for a Neutron Star Nasty Norsemann + 8 Keys

Nickel Sales:

https://backpack.tf/profiles/76561198055622215#!/compare/1587772800/1587945600 - 16 Keys

https://backpack.tf/profiles/76561198055622215#!/compare/1588636800/1588723200 - Australium Sniper Rifle (~28 Keys)

While 37 is now valid, you'll need to include some of the lower sales. The non-Strange Norsemann will need to be priced first before fixing this.