Time Warp Towering Pillar of Hats (100)
https://backpack.tf/stats/Unusual/Towering%20Pillar%20of%20Hats/Tradable/Craftable/70

Sale 1)
https://backpack.tf/profiles/76561198042088457#!/compare/1563494400/1565913600
https://backpack.tf/profiles/76561198161711912#!/compare/1565740800/1565913600 - Bulky

Sale 2)
https://backpack.tf/profiles/76561198010707003#!/compare/1565136000/1565222400
https://backpack.tf/profiles/76561198215327808#!/compare/1565136000/1565222400 - Sold for 90 Keys + ~5 Keys in Sweets + Collector's Jag - Caps at Buyout
Buyout was 100 Keys - https://bot.tf/stats/listings/4KRVE3N8

[i]Mini for Jag:[/i]
https://steamcommunity.com/market/listings/440/Collector%27s%20Jag
Pretty sure with a sale like that this will cap easily

Summary:
100