Green Energy Brigade Helm

yes

Sale 1:

Sold with a Strange (Specialized Killstreak) Australium Flamethrower, Max's Severed Head, and a Vintage Professional Killstreak Sharpened Volcano Fragment for a Cauldron Bubbles Flamboyant Flamenco.

http://backpack.tf/profiles/76561198066177907#!/compare/1467072000/1467331200

Could be used to price the Flamenco.

Sale 2:

SCM?

http://backpack.tf/profiles/76561198128005244#!/compare/1466812800/1466899200

Sale 3:

Sold for 52 keys. Histories don't seem to pick up the keys being owned by the person who bought it, however, suggesting that the person who bought it bought it instantly?

http://backpack.tf/profiles/76561198147063581#!/compare/1461801600/1461974400

The other side's BP wasn't updated until after he got the hat so he probably bought the keys within that time frame.

http://backpack.tf/profiles/76561198150774204#!/compare/1461456000/1461974400

I can confidently say that it sold for 52 keys judging by how nothing else was sold on the seller's side.

There's an extra key and ref that I can only assume came from somewhere else. Nothing points to it being from the Brigade Helm, however.

Sale 3:

Sold with a Steaming Neckwear Headwear for a Secret Fez. Considering its age bordering 3 months, it's probably best to not use it.

http://backpack.tf/profiles/76561198074157780#!/compare/1460419200/1460505600

Taking 52 keys. Easy pure sale and two semi-supportive sales reinforce this.