Oops...

Pricing the unpriced!

Sale 1: http://backpack.tf/profiles/76561198011061869#!/compare/1492992000/1493078400

http://backpack.tf/suggestion/59029d02e3387731696cfa49 - Being used here.

Sale 2: http://backpack.tf/profiles/76561198106182243#!/compare/1492905600/1493078400 - Outlier.

Sale 3: http://backpack.tf/profiles/76561198076641199#!/compare/1492214400/1492300800 - Bulk.

Sale 4: http://backpack.tf/profiles/76561198081960217#!/compare/1492214400/1492560000 - 75 keys

Mini for BoA: http://backpack.tf/suggestion/590daee00e2cad71560392fc - 75

Sale 5: http://backpack.tf/profiles/76561198081960217#!/compare/1493424000/1493856000 - Bulk.

Sale 6: http://backpack.tf/profiles/76561198204215085#!/compare/1493856000/1493942400

Additional proof by Marty:

http://backpack.tf/profiles/76561198079631972#!/compare/1494806400/1494892800 - Sold for KaW Vive, 50

http://backpack.tf/profiles/76561198079631972#!/compare/1494806400/1494892800 - Sold for GE Brain Bowl and sweets, ~54 (credits Foamy, he found this one)

New seller for 65, but only 1 week old: http://www.tf2outpost.com/trade/29195830

With sales at 50, 54, 75, and 83, I would eliminate one sale at each end of the range and go with ~55-75 here.

55-75 it is!