Sale 1:

Sold for 3 keys

https://backpack.tf/profiles/76561199142817642#!/compare/1703376000/1703462400

https://backpack.tf/profiles/76561198113190503#!/compare/1703289600/1703376000

https://backpack.tf/item/11103588880

= 3 keys

Sale 2:

Sold for 3 keys

https://backpack.tf/profiles/76561199029736015#!/compare/1708992000/1709078400

https://gladiator.tf/sales?item=Holy%20Grail%20Taunt:%20The%20Drunken%20Sailor&at=2024-02-28T10:04:42.719Z - labelled as 3 keys.

https://backpack.tf/item/13911037800

Buyer's backpack hasn't been scanned, but it's pretty clear that it sold for 3 keys here. The keys and metal that left the inventory went towards a screaming tiger meet the medic, seen in Sale 1 here:

https://backpack.tf/suggestion/65e40e75bef3d5a6760a5482

= 3 keys

Sale 3:

Sold for 2 keys + 12.22 ref (~0.2 keys)

https://backpack.tf/profiles/76561198311498888#!/compare/1701216000/1701302400

https://backpack.tf/profiles/76561198096163722#!/compare/1700438400/1701302400

https://backpack.tf/item/13784477045

= 2.2 keys

Other Sales:

#1

https://backpack.tf/profiles/76561198274778188 - backpack won't update for me

https://backpack.tf/profiles/76561198311498888#!/compare/1700179200/1700265600

https://backpack.tf/item/13784477045

Untraceable

#2

https://backpack.tf/profiles/76561198114556179#!/compare/1706054400/1706140800

https://backpack.tf/profiles/76561198052648734#!/compare/1705536000/1706140800

https://backpack.tf/item/12605715485

Bulk for GBH Grenadier's Softcap

#3

https://backpack.tf/profiles/76561198189916907#!/compare/1700438400/1705017600

https://backpack.tf/profiles/76561198330682958#!/compare/1701216000/1705190400

https://backpack.tf/item/11415252122

Untraceable, involves a possible auction.

#4

https://backpack.tf/profiles/76561198035332989#!/compare/1701216000/1701302400

https://backpack.tf/profiles/76561199142817642#!/compare/1701216000/1701302400

https://backpack.tf/item/11103588880

Bulk for Demonflame Gibus

#5

https://backpack.tf/profiles/76561199136171109#!/compare/1707696000/1707782400

https://backpack.tf/profiles/76561199621798992#!/compare/1707696000/1707782400

https://backpack.tf/profiles/76561198264020470#!/compare/1707177600/1707868800

https://backpack.tf/profiles/76561199161916038#!/compare/1707782400/1707868800

Hard to pinpoint when this was unusualified (it wasn't prior to any of these), but they're all untraceable anyways.

#6

https://backpack.tf/profiles/76561199201937808#!/compare/1708041600/1708128000

https://backpack.tf/profiles/76561199029736015#!/compare/1708041600/1708128000

https://gladiator.tf/sales?item=Holy%20Grail%20Taunt:%20The%20Drunken%20Sailor&at=2024-02-18T11:08:20.557Z - labelled as 2 keys + 9 ref

https://backpack.tf/item/13911037800

Untraceable

#7

https://backpack.tf/profiles/76561198052648734#!/compare/1708473600/1708732800

https://backpack.tf/profiles/76561198872222015#!/compare/1708646400/1708732800

https://backpack.tf/item/12605715485

Bulk for Time Warp Bloke's Bucket Hat

#8

https://backpack.tf/profiles/76561198872222015#!/compare/1708646400/1708732800

https://backpack.tf/profiles/76561198110801302#!/compare/1708646400/1708732800

https://backpack.tf/item/12605715485

Untraceable

#9

https://backpack.tf/profiles/76561198074041436#!/compare/1708560000/1708819200

https://backpack.tf/profiles/76561198244962432#!/compare/1708473600/1708560000

https://backpack.tf/item/11829708666

Bulk

https://backpack.tf/item/14092054057 - traded between stn bots

https://backpack.tf/item/12422916583 - mannco

https://backpack.tf/item/12126273887 - mannco

Sellers:

https://imgur.com/a/xNedb2Y

https://backpack.tf/item/11829708666 - 3 keys

https://backpack.tf/item/10744959385 - ~7.15 keys

https://backpack.tf/item/11103588880 - 10 keys

https://backpack.tf/item/11982788295 - marketplace

Sales at:

2.2

3 (2x)

Only one sale at 2.2 keys, with buyers at 2.2 keys currently. It's also outdated now. It wasn't when I started working on this suggestion though, so I figured I'd include it anyways.

Taking 3 keys flat.