https://i.imgur.com/MpqMY3Z.png

https://backpack.tf/item/4049015646

$164.00 / $2.25 = 72.9

= 73 keys

Keys prices had several big swings back and forth throughout the day from $2.15 to $2.34. Taking keys at the midpoint of $2.25

73 keys is only slightly above buy orders, but the item had been listed for sale for 2 days already when I bought it (see screenshot) so it doesn't qualify as a quicksell and should be fine to use.