2 of these in existance, 1 on outpost that has sold 4 times. This suggestion captures all 4 of those sales.

http://www.tf2outpost.com/trade/11890752

Sold with Time Warp Snaggle(~3.9) for Secret Birdcage(~9.9 mid price) + 1 bud

9.9 + 1 - 3.9 = ~7 buds - outlier

http://www.tf2outpost.com/trade/12192705

Sold with Time Warp Snaggle(~3.9) for Knifestorm Ballcap(~7)

7 - 3.9 = ~3.1 buds

Proof: http://backpack.tf/id/76561198040487374?time=1372402800 -> http://backpack.tf/id/76561198040487374?time=1372489200

http://www.tf2outpost.com/trade/11819911

Sold for Hearts Trilby(~3.6 buds)

Proof: http://backpack.tf/id/76561198056661356?time=1371452400 -> http://backpack.tf/id/76561198056661356?time=1371625200

http://www.tf2outpost.com/trade/13725406

Sold with Clean Max for Disco Ballcap(no price)

Proof: http://backpack.tf/id/76561198045857997?time=1376809200 -> http://backpack.tf/id/76561198045857997?time=1376895600