Tied for the 12th highest number of a hat with Burning Flames, not counting the extra Dupes.

http://backpack.tf/item/672426206

Sale 1) Sold for a Green Energy Vintage Tyrolean (60.5 Keys) + ~50 Keys of Items + 16 Keys + Nuts and Bolts Detective Noir (12 Keys) + ~3 Keys of Refined

http://backpack.tf/profiles/76561198148511293#!/compare/1477440000/1477526400

60.5 + 50 + 16 + 12 + 3 = 141.5 Keys

Tyrolean Mini

http://backpack.tf/profiles/76561198264853358#!/compare/1477785600/1478131200 - Quicksold for 56 Keys (History: http://backpack.tf/item/3261586311)

http://backpack.tf/profiles/76561198050958150#!/compare/1483833600/1484092800 - Sold for an Ancient Eldritch Hellmet (53 - 62 Keys) + 3 Keys

http://imgur.com/a/EHn77 - Hellmet has a 15 Day Unsold at its current price, and young sellers at 53 and 55 Keys. Taking the Hellmet as between that.

No other decent sales that I could find.

Sale 2) Sold for a Circling Hearts Brainiac Hairpiece + Duped Circling Hearts Big Country

http://backpack.tf/profiles/76561197993976532#!/compare/1478995200/1479081600

Fits in the range.

http://backpack.tf/item/954984269

Sale 3) Sold for a Duped Burning Flames Le Party Phantom + Duped Sunbeams Fancy Fedora

http://backpack.tf/profiles/76561198123530264#!/compare/1479168000/1480032000

http://www.tf2outpost.com/trade/28606520 - Capped by the Buyout of 160 Keys

Sale 4) Sold for 88 Keys + Scorching Flames Flipped Trilby

http://backpack.tf/profiles/76561197993826799#!/compare/1483574400/1483747200

http://www.tf2outpost.com/trade/28615937 - Capped by the Buyout of 150 Keys

http://backpack.tf/item/277398724

Sale 5) Sold + Bubbling Cold Killer (27 Keys) for a Scorching Flames Troublemaker's Tosslecap (167.5 Keys)

http://backpack.tf/profiles/76561198045309178#!/compare/1478304000/1478390400

167.5 - 27 = 140.5, which I'll round to 140 Keys

Scorching Tosslecap Mini

http://backpack.tf/suggestion/586439420e2cad6e514a4b68 - 167.5 Keys