Buyers :

http://www.tf2outpost.com/trade/9175636 (quick buying unique for 3 keys)

http://www.tf2outpost.com/trade/9200933 (buying Gen/unique for 3 keys)

http://www.tf2outpost.com/trade/9160720 (buying unique for 3 keys)

http://www.tf2outpost.com/trade/9122781 (possible 3 keys for unique)

http://www.tf2outpost.com/trade/9199980 (offered ebenezer = 3.5 keys)

http://www.tf2outpost.com/trade/9199759 (offered OBI + key = 2.5 keys)

No sell prices currently, but this is what buyers are buying the item for.

Needs to start somewhere.

This is a repost, it was apparent that there should not be a range of 2.5-3 keys. Rather just 3 keys flat.