Really tricky item to put an accurate price on, but it's abundantly clear that you're not going to get 1 key for this. Most people how sell at 2.33, with a few having success, and some have dropped to 2 and lower.

Unsold for 1 key

http://www.tf2outpost.com/trade/7817271 - Unsold for 1 key

http://www.tf2outpost.com/trade/7880289 - Unsold for 1 key

http://www.tf2outpost.com/trade/7862180 - Unsold for 1 key

http://www.tf2outpost.com/trade/7607177 - Unsold for 1 key

http://www.tf2outpost.com/trade/7790159 - Unsold for 1 key

Unsold for 3 ref

http://www.tf2outpost.com/trade/7830828 - Unsold for 3 ref

http://www.tf2outpost.com/trade/7860392 - Unsold for 3 ref

http://www.tf2outpost.com/trade/7875307 - Unsold for 3 ref

Unsold for 2.66

http://www.tf2outpost.com/trade/7857455 - Unsold for 2.66

http://www.tf2outpost.com/trade/7838954 - Unsold for 2.66

http://www.tf2outpost.com/trade/7865908 - Unsold for 2.66

Sold/Selling for 2.33 ref

http://www.tf2outpost.com/trade/7789762 - Selling for 2.33

http://www.tf2outpost.com/trade/7790159 - Selling for 2.33

http://www.tf2outpost.com/trade/7784524 - Selling for 2.33

http://www.tf2outpost.com/trade/7862672 - Selling for 2.33

http://www.tf2outpost.com/trade/7876654 - Selling for 2.33

http://www.tf2outpost.com/trade/7841173 - Sold for 2.33

Sold/Selling for 2 ref

http://www.tf2outpost.com/trade/7818537 - Sold for 2 ref

http://www.tf2outpost.com/trade/7877966 - Selling for 2 ref

http://www.tf2outpost.com/trade/7860456 - Selling for 2 ref

Definitely needs a drop, best range that I could produce while excluding the outliers.