I'm a horrible person.

1st suggestion was 36 keys, then they said the overpay was not needed, then they said you need it.

Sold for a vivid plasma your worst nightmare (~40).

Outpost trade http://www.tf2outpost.com/trade/27433020

Before: http://backpack.tf/profiles/76561198025963071?time=1447574400

After: http://backpack.tf/profiles/76561198025963071?time=1447660800

This is the only recent sale, the only other for sale is asking 70 keys and hasn't sold for over 10 months.

40*0.9= 36

If this suggestion fails, then this sale Isn't that useful to price this