Aliens!

http://backpack.tf/item/4245231128

Sale 1) Sold + 29 Keys for a Circling Hearts Brainiac Hairpiece (147.5 Keys)

http://backpack.tf/profiles/76561197977828464/#!/compare/1456732800/1456819200 - Seller

http://backpack.tf/profiles/76561198109272505/#!/compare/1456646400/1456732800 - Buyer

147.5 - 29 = 118.5 Keys, which rounds to 120 Keys

Brainiac Hairpiece Mini

http://backpack.tf/vote/id/56fb47f3c440457c39520847 - 147.5 Keys

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http://backpack.tf/item/4333263171

Sale 2) Sold for a Subatomic Phononaut (96 Keys)

http://backpack.tf/profiles/76561198045414411/#!/compare/1457424000/1457856000

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http://www.tf2outpost.com/trade/27995251 - Seller for 90 Keys

https://gyazo.com/ab481255bdd8588f35786d86cba0a98f - Seller for 90 Keys

Given those 2 Sellers at 90 Keys, I'll take 120 as an Outlier, per Randy's thoughts.