Finally, only took me about 5 days.

Sale 1:

Sold for Stormy Storm Law (72)

No outpost

Seller: https://backpack.tf/profiles/76561198216561389#!/compare/1508803200/1508889600

Buyer: https://backpack.tf/profiles/76561198048399031#!/compare/1508803200/1508889600

X = 72

Sale 2:

Sold for Scorching Nano (Suggestion at 42) + ~25 keys in metal/items

No outpost

Seller: https://backpack.tf/profiles/76561198205939253#!/compare/1508457600/1508630400

Buyer: https://backpack.tf/profiles/76561198113394590#!/compare/1508371200/1508630400

X = 67

Sale 3:

Sold for Green Energy Private Eye (Mini at 42.5 below) + 16 keys

No outpost

Seller: https://backpack.tf/profiles/76561198132538195#!/compare/1504915200/1505001600

Buyer: https://backpack.tf/profiles/76561198141219789#!/compare/1504742400/1504915200

X = 59

Sale 4:

Sold for Circling Heart Hot Doggerson (Suggestion at 56)

No outpost

Seller: https://backpack.tf/profiles/76561198141219789#!/compare/1504915200/1505001600

Buyer: https://backpack.tf/profiles/76561198268005140#!/compare/1504915200/1505001600

X = 57

Sale 5:

Sold for 52 keys

http://www.tf2outpost.com/trade/29240359 - B/O of 54

Seller: https://backpack.tf/profiles/76561197990986202#!/compare/1504569600/1504742400

Buyer: https://backpack.tf/profiles/76561198132538195#!/compare/1504742400/1504828800

X = 52

Sale 6:

Sold for 47 keys

http://www.tf2outpost.com/trade/29410843 - No visible B/O

Seller: https://backpack.tf/profiles/76561198027694776#!/compare/1509494400/1509580800

Buyer: https://backpack.tf/profiles/76561198116448555#!/compare/1509494400/1509580800

X = 47

Sale 7:

Sold for Orbiting Fire Killer Exclusive (Suggestion at 38)

No outpost

Seller: https://backpack.tf/profiles/76561198190084707#!/compare/1508198400/1508284800

Buyer: https://backpack.tf/profiles/76561198205939253#!/compare/1508198400/1508284800

X = 38

Sale 8:

Sold for Circling Heart Hermes + 3 keys

No outpost

Seller: https://backpack.tf/profiles/76561198048399031#!/compare/1508803200/1508889600

Buyer: https://backpack.tf/profiles/76561198027694776#!/compare/1508803200/1508889600

Couldn’t find a usable sale on the Hermes. Can be used to update it instead.

Sale 9:

Bulk for Eldritch Pullover

Seller: https://backpack.tf/profiles/76561198113394590#!/compare/1508371200/1508630400

Buyer: https://backpack.tf/profiles/76561198216561389#!/compare/1508544000/1508630400

Sale 10:

Sold with ~22 keys in items for Strange Green Confetti Killer Exclusive

Seller: https://backpack.tf/profiles/76561198268005140#!/compare/1505692800/1505779200

Buyer: https://backpack.tf/profiles/76561198086948995#!/compare/1505606400/1505779200

Can be used to price that thing

Sale 11:

Sold for Purple Confetti Brainiac Hairpiece + 3 keys

Seller: https://backpack.tf/profiles/76561198342161127#!/compare/1507939200/1508025600

Buyer: https://backpack.tf/profiles/76561198190084707#!/compare/1508025600/1508112000

No mini available on the Brainiac. Can be used to update it instead.

Circling Heart Hot Doggerson:

https://backpack.tf/suggestion/5a0d7309cf6c7554de415f85

Green Energy Private Eye Mini:

https://backpack.tf/suggestion/59f2d946cf6c7551d87f1645 - See my comment

Orbiting Fire KE:

https://backpack.tf/suggestion/5a0d5da9cf6c7554ef54fef7

Scorching Nano:

https://backpack.tf/suggestion/5a0d6f6d44325a127955a183

Sellers:

57 keys:

https://i.imgur.com/bb0yJGO.png

https://backpack.tf/item/916977601 - re-listed over the course of 3 months

59 keys:

https://i.imgur.com/2shH9rQ.png - 19 days

75 keys:

https://i.imgur.com/zSVNBBq.png

https://backpack.tf/item/3977525208 - re-listed over the course of ~6 months

https://i.imgur.com/4JOi1bA.png - 2 months

Sales at:

38

47

52

57

59

67

72

38 seems very low, and I’m pretty sure scrap.tf pays more. Excluding 38.

Sellers at 57 and 59 show that it will not sell well for more than that price. Excluding 67 and 72. (hat in the 72 sale seems very overpriced, and sale at 67 had no B/O anyways).

Going with 47-59.