Actually would not make a bad Halloween costume...

Classifieds (As of 11:45 PM EST):

2 at 3.55 ref, 2 at 3.66 ref and 8 at 2 ref http://prntscr.com/6dpaal

About a page and a fourth on Outpost, only about half of which are not selling for offers or have low craft numbers.

Unsuccessful sellers:

http://www.tf2outpost.com/trade/25228824 4 ref

http://www.tf2outpost.com/trade/25278250 "Bp.tf prices"

http://www.tf2outpost.com/trade/25112118 "bp.tf price"

Seller below the current price:

http://www.tf2outpost.com/trade/25237925 3.66 ref

Recent sale:

http://www.tf2outpost.com/trade/25197042 4 ref

As 3.66 hasn't sold, but 4 ref still sells occasionally, the more conservative 3.66 to 4 should suffice.