Sale #1:

https://backpack.tf/profiles/76561198179707937#!/compare/1544745600/1544832000

Sold for 27 keys

27 keys

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Sale #2:

https://backpack.tf/profiles/76561198100128947#!/compare/1544227200/1544313600

Sold with 3 keys for a Miami Nights Noble Amassment of Hats (28 keys)

25 keys

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Minis:

Miami Nights Noble Amassment of Hats:

https://marketplace.tf/shopitem/xadadada/137;5;u61

Sold for $54.99 on January 26, 2019.

$54.99 / $1.80 = 30.55

31 keys

Since B/O was 28 keys (https://i.imgur.com/dcC1rHC.png), going with 28 keys.