I GOT PREMIUM!!! THANKS JORDAN. <3 :D

4 month old price!

Sale 1:

Sold for 55 keys

http://www.tf2outpost.com/trade/25869830

http://backpack.tf/profiles/76561198101197890?time=1431673200 - before

http://backpack.tf/profiles/76561198101197890?time=1431759600 - after

~Backpack histories don't show all 55 keys but the trade comments reinforce that it was sold for 55 keys.

Sale 2:

Sold for Bubbling Little Buddy* (16.5*0.9) + 4 buds (4*8) = 14.85 + 32 = 46.85 (rounding to 47 keys) (buds were 8 keys)

http://www.tf2outpost.com/trade/25260954

http://backpack.tf/profiles/76561198031569942?time=1427526000 - before

http://backpack.tf/profiles/76561198031569942?time=1427612400 - after

Sale 3: (invalid sale, was used to price the Muffs)

Sold with Demonflame Private Eye + Sunbeams Tyrant's Helm for Spellbound Tough Stuff Muffs

http://www.tf2outpost.com/trade/25805924

http://backpack.tf/profiles/76561198043781630?time=1430204400 - before

http://backpack.tf/profiles/76561198043781630?time=1430290800 - after

Mini-suggestion for Bubbling Little Buddy*:

http://www.tf2outpost.com/trade/25260236 - Sold for Peace Sign Football Helmet = ~17 keys

http://www.tf2outpost.com/trade/25937351 - B/O of 16 keys (5 days)

~Taking a value of 16.5 keys.

Notes:

http://www.tf2outpost.com/trade/25832700 - B/O of 55 keys

Conclusion:

Two valid sales at 47 and 55 keys, alongside with a B/Os of 55 keys. Taking a final range of 47-55 keys.

Feel free to support/counter my suggestion!