Sold with 80 keys for duped Sunbeams Modest Pile of Hat (220 * .9):

220 * .9 - 80 = 118 keys

http://backpack.tf/profiles/76561198062643826?time=1434438000 (June 16th)

http://backpack.tf/profiles/76561198062643826?time=1434783600 (June 20th)

Sold with Steaming Killer Exclusive (40) for duped Cloudy Moon Modest Pile of Hat (~150):

150 - 40 = 110 keys

http://backpack.tf/profiles/76561198062457737?time=1435388400 (June 27th)

http://backpack.tf/profiles/76561198062457737?time=1435474800 (June 28th)

Sellers at 135 keys:

http://www.tf2outpost.com/search/251199918

Using 110 keys for Vivid Plasma Soldier's Stash. Estimation should be close.

Duped Cloudy Moon Modest Pile of Hat:

Sellers between 140 - 160:

http://www.tf2outpost.com/search/251199884

Strange Professional Killstreak Australium Rocket Launcher:

http://backpack.tf/classifieds/?tradable=1&craftable=1&australium=1&item=Rocket%20Launcher&quality=11&killstreak_tier=3

Frostbite Le Party Phantom:

Sold for duped Searing Plasma Pyromancer's Mask (80 * 9):

http://backpack.tf/profiles/76561198154067107?time=1436252400 (July 7th)

http://backpack.tf/profiles/76561198154067107?time=1436338800 (July 8th)

80 * .9 * .9 = 64.8 keys

~65 keys

Sold for Hellfire Cosa Nostra Cap (56) + Smoking Prussian Pickelhaube (16):

http://backpack.tf/profiles/76561198035334988?time=1436252400 (July 7th)

http://backpack.tf/profiles/76561198035334988?time=1436425200 (July 9th)

(56 + 16) * .9 = 64.8 keys

~65 keys

Sold for Bubbling HazMat Headcase (75):

http://backpack.tf/profiles/76561198180484678?time=1436079600 (July 5th)

http://backpack.tf/profiles/76561198180484678?time=1436166000 (July 6th)

75 * .9 = 67.5 keys

~65 keys