Apparently one of one to exist based on backpack.tf's findings [http://backpack.tf/item/2035788438]
3 months ago (Latest - possibly outdated)
http://www.tf2outpost.com/trade/17385116
Sold for the contents of (http://www.tf2outpost.com/trade/17457695) - Time Warp Fedora (6.2) + S.F Scattergun (2.7) + S.F. Bat (~.95 buds) > ~10 Buds
2 months ago (most recent)
http://www.tf2outpost.com/trade/17569458
Sold for a c9 Heers Helm 
(Unpriced, Evidence shows sales of anywhere from 10 to 12 buds at