I got the horses in the back.

https://backpack.tf/item/1349458773

Sale 1) Sold for $29.86 when Keys were ~$1.80 each

https://marketplace.tf/items/tf2/379;5;u35

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

High outlier.

https://backpack.tf/item/2243235708

Sale 2) ?

https://backpack.tf/profiles/76561198912544809#!/compare/1551398400/1556668800

https://backpack.tf/item/1385486893

Sale 3) Sold for 14 Keys

https://backpack.tf/profiles/76561198043826027#!/compare/1555632000/1555718400

Sale 4) Sold for a Smoking Bomb Beanie (11.5 Keys)

https://backpack.tf/profiles/76561198208761289#!/compare/1555718400/1555804800

Rounds to 12 Keys

Beanie Mini

https://backpack.tf/profiles/76561198102292713#!/compare/1559001600/1559088000 - Sold for a Strange Dead Presidents Elf Esteem + ~0.6 Keys of Refined

https://backpack.tf/profiles/76561198290081434#!/compare/1560384000/1560470400 - Sold for a Vivid Plasma Elf Esteem

https://imgur.com/a/5tFPtNW - Vivid Elf has Sellers at 10.6 - 11 Keys

https://marketplace.tf/items/tf2/30823;5;u35 - Sold for $22.22 when Keys were ~$1.84 each (22.22 / 1.84 = ~12 Keys)

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

Taking 11.5 Keys.

Strange Dead Presidents Elf Esteem Micro

https://backpack.tf/profiles/76561198176670029#!/compare/1560038400/1560124800 - Sold for a Green Confetti Flipped Trilby (10.25 Keys)

Sale 5) Bulk sale for a Smoking Brim Full of Bullets

https://backpack.tf/profiles/76561198131479738#!/compare/1555718400/1555804800

https://backpack.tf/profiles/76561198158206236#!/compare/1555718400/1555804800

Sale 6) Sold for a Miami Nights Rimmed Raincatcher + 1 Key + ~0.6 Keys of Items

https://backpack.tf/profiles/76561198158206236#!/compare/1558828800/1558915200

Fits in the range.

Raincatcher Mini

https://backpack.tf/profiles/76561198323565601#!/compare/1558051200/1558137600 - Sold for 11 Keys

https://imgur.com/a/RiTD6fu - Sellers at 12 - 13 Keys, Buyers at 10.2 Keys

https://backpack.tf/item/3337604497

https://backpack.tf/item/4443111521

https://backpack.tf/u/76561198323565601

https://backpack.tf/u/76561198349886701

https://backpack.tf/u/76561198817510262

Sale 7) Sold for a Green Confetti Ye Olde Baker Boy (11.5 Keys)

https://backpack.tf/profiles/76561198268386810#!/compare/1558828800/1558915200

Rounds to 12 Keys

Baker Mini

https://backpack.tf/suggestion/5d1a4ac46780727ca25f3d44 - 11.5 Keys

Sale 8) Sold for a Fountain of Delight Soviet Strongarm + Strange Double Spelled Grenade Launcher (~3 Keys)

https://backpack.tf/profiles/76561198291041323#!/compare/1558828800/1558915200

Low outlier.

Strongarm Mini

https://marketplace.tf/items/tf2/30844;5;u3005 - Sales hover around 7 Keys

https://imgur.com/a/A2wU4Uj - Sales from 4 - 7 Keys

https://backpack.tf/profiles/76561198335791307#!/compare/1558828800/1558915200 - This is the 7 Key sale

Sale 9) Sold for a Blizzardy Storm Western Wear

https://backpack.tf/profiles/76561198932518745#!/compare/1558915200/1559001600

This can be used for either of these sales.

Sale 10) Bulk sale for a Green Energy Hetman's Headpiece

https://backpack.tf/profiles/76561198246208014#!/compare/1559779200/1559952000

Sale 11) ?

https://backpack.tf/profiles/76561198267189538#!/compare/1561680000/1561766400

https://backpack.tf/profiles/76561198385962271#!/compare/1561248000/1561766400