Sales at ~56 and ~59 here:

https://marketplace.tf/items/tf2/31247;5;u218

The 30 key buyer relisted it for what appears to be 27 keys:

https://next.backpack.tf/classifieds/snapshots/Polar%20Forecast%20Merry%20Cone/65d68e95a81a51a43a0a462f --- 23.29 keys after key price change

https://next.backpack.tf/classifieds/snapshots/Arachne's%20Web%20Legendary%20Lid/65d77e5a85acd76dd10a4e8b --- this was listed for 650 keys (and is still listed for 650), but appears as 560.8

Using the conversion rate (650/560.8), the Merry Cone listing comes out at 27. This sale is untraceable but it is fair to assume it won't be above 27:

https://backpack.tf/profiles/76561198093831749#!/compare/1708300800/1708732800

https://backpack.tf/profiles/76561198091502579#!/compare/1708300800/1708473600

So with sales at 27 (?), 30, 56 and 59 this is best left unpriced.