Big Price gap, I know, but arcana is a rare effect and this hat is 1 of 1, so it has good reasoning to go up in price. I'm not including the 150 key sale because it happened 9 months ago as of this price suggestion opening which should make it invalid to use in the suggestion, so 300 it is!

Proof of sale:

Seller: https://backpack.tf/profiles/76561198118235963#!/compare/1593561600/1593820800

Buyer: https://backpack.tf/profiles/76561198218063977#!/compare/1593043200/1593820800

Note: Doesn't seem like the buyer's backpack loaded until the 4th of July.

Actual Trade: https://imgur.com/yhMEUtJ

Note: This was the 300 key trade which made it too big to get all the keys in the image.

Doesn't seem like the buyer is selling the unusual any time soon considering it's a collector.