https://backpack.tf/item/8227622335

Sale 1) Better for the Headsplitter

https://backpack.tf/profiles/76561198048046849#!/compare/1586736000/1586822400

https://backpack.tf/profiles/76561197994697258#!/compare/1586736000/1586822400

https://backpack.tf/item/8220545614

Sale 2) Sold + 17 Keys for a Snowblinded Blast Defense

https://backpack.tf/profiles/76561198096856475#!/compare/1586476800/1586822400

https://backpack.tf/profiles/76561198061440669#!/compare/1586649600/1586736000

The Snowblinded one doesn't have a great mini (only sale is 120 Keys), so excluding this sale.

https://backpack.tf/item/8165529248

Sale 3) Sold for a Pro KS Aussie Sticky (~28 Keys) + Infernal Flames Skullcracker (19.5 Keys) + 17 Keys

https://backpack.tf/profiles/76561198325595749#!/compare/1586131200/1586217600

28 + 19.5 + 17 = 64.5, which rounds to 65 Keys

Sale 4) Bulk sale

https://backpack.tf/profiles/76561198838788284#!/compare/1588982400/1589068800

Sale 5) Sold for a Death at Dusk Whoopee Cap (57.5 Keys) + Smoking Crack Pot (28 Keys)

https://backpack.tf/profiles/76561198118157202#!/compare/1590278400/1590364800

57.5 + 28 = 85.5, which can be rounded to 85 Keys

Crack Mini

https://backpack.tf/suggestion/5efc0c7de1fb005e5549792b

Sale 6) Better for the Elf

https://backpack.tf/profiles/76561198067893369#!/compare/1590969600/1591056000