10 month old price, 4 exist on market.

I round up.

http://www.tf2outpost.com/trade/17459028

SOLD: SF Knife + SF Ambassador, seller added 2 keys

(1.2 buds)

http://www.tf2outpost.com/trade/18381307

SOLD: 15 keys + S Pomson

(0.9 buds)

http://www.tf2outpost.com/trade/18622681

Offer: TF Logo Rack, seller adds 5 keys

(1.1 buds)

http://www.tf2outpost.com/trade/11717480

Offers:

Australium Knife (1.5 buds)

25 keys (1.3 buds)

22 keys (1.1 buds)

Some sales are a bit low, but recent offers mostly value up to a bud or so. I hope you can understand my range from the evidence I provided.