http://www.tf2outpost.com/trade/25806737 Sold for 45 keys pure in 2 days. (Guess it is relatively quick so wont use it here and it is almost 3 months old.).

Just to remind you that you should not be applying overpay on pure. You added the value of the unusual together with the pure and applied *0.9. This shouldn't be the case. (78 * 0.9 = 70 keys) + 10 keys = 80 keys.

It doesn't matter too much here but in future suggestion please keep this in mind.