My first time doing this kind of suggestion. Good luck to me.....

3.5 Solds/Sellers:

http://www.tf2outpost.com/trade/18885769 - Guy buying it for 3.5 keys (Unsold)

4 key solds:

http://www.tf2outpost.com/trade/18898123 - Added for 4 keys (Sold for that I guess)

http://www.tf2outpost.com/trade/18930630 - 4 keys

There is less than a page in outpost.

Please correct me if I have invalid links ,broken links ,duped links or anything plain wrong.

Extra proof for my range is appreciated ,as is Counter-proof.