I can found 3 sold, because it's a very new hat.

Sale #1:

Sold for a Circling TF Logo Otolaryngologist's Mirror(13-15 key), for an Australium Blutsauger(6 - 6.15 key), for a Vintage Physician's Procedure Mask(24.77 - 26,33 ref), for a Strange Killstreak Silver Botkiller Medi Gun Mk.I($2.03; 22.97 ref) and for some 1 - 7 ref item.

https://backpack.tf/profiles/76561198097921285#!/compare/1524182400/1524268800

Sale #2:

Sold for 14 key pure

https://backpack.tf/profiles/76561198069559160#!/compare/1524355200/1524441600

Sale #3:

Sold with a Taunt: Rock, Paper, Scissors(17.77 - 17.88 ref), with a The Cranial Carcharodon(4.22 – 4.33 ref) and with a Sweet Smissmas Sweater(4.66 – 4.77 ref) for a Purple Confetti Safe'n'Sound(18 key)

https://backpack.tf/profiles/76561198097921285#!/compare/1524355200/1524441600