You missed a few sales, just redo the suggestion and use this:

Scorching Flames Shutterbug: https://backpack.tf/stats/Unusual/Shutterbug/Tradable/Craftable/14

Mini for this: https://backpack.tf/stats/Unusual/Backbiter's%20Billycock/Tradable/Craftable/82

Sale 1:

https://backpack.tf/profiles/76561198103361840#!/compare/1565308800/1565395200

https://backpack.tf/profiles/76561198129995083#!/compare/1565308800/1565395200

= Stormy Storm Charmer's Chapeau (31 keys) + Burning Flames Polar Bear (46 keys) + 15 keys

= 92 keys

Sale 2: (the trade the mini is based on)

https://backpack.tf/profiles/76561198103361840#!/compare/1565308800/1565395200

https://backpack.tf/profiles/76561198044547547#!/compare/1565308800/1565395200

Sale 3:

https://backpack.tf/profiles/76561198401918732#!/compare/1565136000/1565222400

https://backpack.tf/profiles/76561198044547547#!/compare/1565136000/1565222400

= Green Confetti Noble Nickel Amassment of Hats (19.5 keys) + Vivid Plasma Milkman (18.5 keys) + 5 keys + ~1 key in sweets

= 44 keys

Sale 4:

https://backpack.tf/profiles/76561198254487535#!/compare/1564790400/1564963200 (credits to visionz)

https://backpack.tf/profiles/76561198095022965#!/compare/1564876800/1564963200

= 50 keys + Kill-a-Watt Deep Cover Operator (32 keys)

= 82 keys

~ 80 keys (b/o was 80 keys)

Sale 5:

https://backpack.tf/profiles/76561198095022965#!/compare/1564531200/1564617600

https://backpack.tf/profiles/76561198057809362#!/compare/1564444800/1564617600

Bulky/untraceable (buyers at 40 keys for shutterbug https://imgur.com/a/gCsznHR and there were 2 more unusuals traded with the shutterbug)

Sale 6:

https://backpack.tf/profiles/76561198862571271#!/compare/1565049600/1565136000 (credits to visionz)

= 70 keys

Sale 7:

https://marketplace.tf/items/tf2/31048;5;u14 (Aug 6th)

https://marketplace.tf/items/tf2/5021;6

= $223 / $1.84

= 121.19...

~ 121 keys

Key sales summary: 44, 70, 80, 92, 121

Conclusion: excluding 44 and 121, pricing at 70-92 keys