Sale #1:

https://backpack.tf/profiles/76561198151901778#!/compare/1550275200/1550361600

Sold for 11 keys.

11 keys

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Sale #2:

https://backpack.tf/profiles/76561198308772967#!/compare/1554508800/1554681600

Sold for 11 keys.

11 keys

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Sale #3:

https://backpack.tf/profiles/76561198031743044#!/compare/1549324800/1549411200

Untraceable.

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Sale #4:

https://backpack.tf/profiles/76561198031743044#!/compare/1551657600/1551744000

Sold with 4 keys for a Starstorm Slumber Wing Mann (9.5 keys).

5.5 keys

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Minis:

Starstorm Slumber Wing Mann:

https://bot.tf/stats/item?def=30809&q=5&ef=Starstorm+Slumber&craft=1&aus=0&ks=0

https://backpack.tf/profiles/76561198830746068#!/compare/1555020000/1555106400

Sold for 9 keys and 30 ref.

9.5 keys

Sales:

5.5, 11, 11. Going with 5.5 - 11 keys.