Sale #1:

http://www.tf2outpost.com/trade/26171210

Sold for 31 keys, or around there anyways

http://backpack.tf/profiles/76561198064413964?time=1434265200 (June 14th)

http://backpack.tf/profiles/76561198064413964?time=1434351600 (June 15th)

Sale #2:

http://www.tf2outpost.com/trade/25827393

Sold for 6 buds (24) + White Bill's (3) + 6 keys

http://backpack.tf/profiles/76561198107090195?time=1431068400 (May 8th)

http://backpack.tf/profiles/76561198107090195?time=1431154800 (May 9th)

((24 + 3) * 0.9) + 6 = 30 keys

Sale #3:

Sold for a MN Robo Towering (outdated and probably an outlier)

http://backpack.tf/profiles/76561198058368041?time=1432018800 (May 19th)

http://backpack.tf/profiles/76561198058368041?time=1432191600 (May 21st)

Sale #4:

http://www.tf2outpost.com/trade/25955170

Sold with Genuine Point and Shoot (2) for a Mallard Tricorne (needs updating)

http://backpack.tf/profiles/76561198118686035?time=1431846000 (May 17th)

http://backpack.tf/profiles/76561198118686035?time=1432018800 (May 19th)

Tricorne: http://www.tf2outpost.com/trade/25964840