Item 1:

https://backpack.tf/item/16789059169

Sale 1:

https://backpack.tf/profiles/76561198237337976#!/compare/1772841600/1772928000

https://backpack.tf/profiles/76561198063658197#!/compare/1772841600/1772928000

Doesn't show up on either side. Buyer did have a buy order at 9 though so it may have sold for that?

Sale 2:

https://backpack.tf/profiles/76561198063658197#!/compare/1773273600/1773446400

https://backpack.tf/profiles/76561198324290571#!/compare/1773273600/1773360000

Buyer from previous sale listed it straight on MP then sold on MP

https://marketplace.tf/items/tf2/31593;5;u29

Sold for $29.99 on the 13th of March

Keys were $1.9 on the 13th

29.99/1.9

= 15.7

Rounding up to 16 keys

Item 2:

https://backpack.tf/item/16760163478

Sale 3:

https://backpack.tf/profiles/76561198824961828#!/compare/1771977600/1772409600

https://backpack.tf/profiles/76561197976392732#!/compare/1771891200/1771977600

Sold for 11 keys pure (ID 16760214299) (Credits Deller)

//

Sellers:

BPTF - https://imgur.com/a/LdHfVXo - 1 @ 20 keys

MPTF - https://marketplace.tf/items/tf2/31593;5;u29 - None

STN - https://stntrading.eu/item/tf2/Unusual+Stormy+Storm+Epilogue+Locks - None

SCM - https://imgur.com/a/lJ4ypji - https://steamcommunity.com/market/listings/440/Mann%20Co.%20Supply%20Crate%20Key - 1 @ $45.34AUD (~13 keys) 1 @ $76.17AUD (~22 keys)

Sale(s):

11, 16

Even though there is a SCM seller at 13 I am not going to exclude the higher sale. Especially since its pretty much directly in the middle between the two.

Going with 11 - 16 keys