The Mask.

Classified ads at the time of posting:

Page 1 - http://m.imgur.com/ZN57j4s

Page 2 - http://m.imgur.com/hSboM1g

http://backpack.tf/classifieds?item=Noh+Mercy&quality=1&tradable=1&craftable=1

1*1.06 keys

2*1.1 keys

8*1.12 keys

1 buy order at 1.06 keys

Unsold at 1 key and 3 refined (~1.2 keys):

http://www.tf2outpost.com/trade/27323481 (~1 week)

Unsold at 18.55 refined (~1.15 keys):

http://www.tf2outpost.com/trade/27297716 (~1 week, poorly bumped)

Unsold at 1.15 keys:

http://www.tf2outpost.com/trade/27363495 (~1 day, young)

Unsolds at Backpack tf price:

http://www.tf2outpost.com/trade/27361616 (~1 day, young)

http://www.tf2outpost.com/trade/27342422 (~4 days, never bumped)

Seller at 1.1 keys:

http://www.tf2outpost.com/trade/27346347 (~3 days old)

Seller at 1 key and 1 refined (~1.05 keys):

http://www.tf2outpost.com/trade/27342720 (~4 days old)

This is all I could find on Outpost that are valid at the time of posting this suggestion.