I bought this!

Item 1:

https://backpack.tf/item/12133923892

Sale 1:

https://mannco.store/item/440-scorching-flames-unusual-all-hallows-hatte

https://imgur.com/a/lX1CqVA

$890 / $1.67 = 532.934 keys

This is my first time submitting a suggestion so please let me know if I made a mistake and I will resubmit.

I was unaware that mannco is not valid for pricing anymore. I find this a little strange as the price graph can be viewed on the website and I am able to prove this sale happened, but am ultimately going to close this if it is against the rules. My apologies.