Item 1:

https://backpack.tf/item/12161163103

https://backpack.tf/profiles/76561199084367825#!/compare/1754092800/1755043200

Bought between quicksell bots (moved 1 day after)

Item 2:

https://backpack.tf/item/6762051163

Sale 1:

https://marketplace.tf/items/tf2/30984;5;u18

Sold for $19.99 on the 20th of July

Keys were $2.01 on the 20th

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

19.99/2.01

= 9.94

Rounding up to 10 keys

//

Sellers:

BPTF - https://imgur.com/a/uaHIXUM - 1 @ 9.57 keys

MPTF - https://marketplace.tf/items/tf2/30984;5;u18 - None

STN - https://stntrading.eu/item/tf2/Unusual+Circling+Peace+Sign+Sky+High+Fly+Guy - None

SCM - https://steamcommunity.com/market/listings/440/Unusual%20Sky%20High%20Fly%20Guy?filter=Circling+Peace - https://imgur.com/a/H0fdnmH - 1 @ $50.91AUD (~14.38 keys)

Sale(s):

10

Due to the unsold at 9.57 (rounding to 9.5) including this into range.

Going with 9.5 - 10 keys