Sale #1:

https://backpack.tf/profiles/76561198097135729#!/compare/1552176000/1552608000

Sold with 90 keys for a Death at Dusk Brotherhood of Arms (190 keys).

100 keys

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Sale #2:

https://backpack.tf/profiles/76561198846276257#!/compare/1552694400/1552780800

Sold for 51 keys.

Sales:

51, 100. Seller at 50 keys determines low end (https://i.imgur.com/vPfWSI0.png).