There's probably an undercutting war going on, dropping from ~280 to 250 now over the course of a couple of weeks. In total, there are 3 sellers below 320, so its likely that's gonna end up high. As a result, the range is probably on the high side here, especially since a lower sale is excluded already.

Couple of new sales (Courtesy of Shuffle Spy):

https://backpack.tf/profiles/76561198045883624#!/compare/1621468800/1621555200 - Bulk

https://backpack.tf/profiles/76561198026372829#!/compare/1618704000/1619568000 - Drop that

https://backpack.tf/profiles/76561198026372829#!/compare/1619740800/1620172800 - Backpack dump

https://backpack.tf/profiles/76561198190868126#!/compare/1619568000/1619740800 - Roughly 300?

https://backpack.tf/profiles/76561198045343680#!/compare/1620518400/1620604800 - Probably mid-200s

https://backpack.tf/profiles/76561197961169520#!/compare/1621036800/1621123200 - Bulk

I feel this will need some polishing, and given the current market it may be best to wait and see what happens there before pricing this.