Rebooting, proof in the comments.

*Disclaimer*

I went on Outpost to see how the sale was going for the item, but I found out there were many unsold at 2 keys prices.

So, I decided to check how many were buying them for the price. I found out nearly all were buying them for lowball prices.

But this was all the proof I could fine to prove the price.

*BUYING*

http://www.tf2outpost.com/trade/8398003 ( buying for 6 ref. )

"Pretty much the only fair price I could find, without it being a buy-quick price." :/

*UNSOLD*

http://www.tf2outpost.com/trade/8299888 ( unsold for 5 days at 2 keys )

http://www.tf2outpost.com/trade/8119934 ( unsold for 1 week at 2 keys )

http://www.tf2outpost.com/trade/8408515 ( unsold for 1 day at 2 keys )

http://www.tf2outpost.com/trade/8406028 ( unsold for 1 day at 2 keys )

http://www.tf2outpost.com/trade/8051780 ( unsold for 2 weeks at 2 keys )

http://www.tf2outpost.com/trade/8189594 ( unsold for 1 week at 2 keys )

http://www.tf2outpost.com/trade/8387473 ( unsold for 1 day at 2 keys )

http://www.tf2outpost.com/trade/8202632 ( unsold for 1 week at 1 key + 3 ref )

"The lowest seller on Outpost with this item." :/

Conclusion: 2 keys is too high. No one is buying them for 2 keys any more, but not many are buying them either, except for one at 6 ref. That is my conclusion.