5 months old price

http://backpack.tf/classifieds/search/976/6/0 - Three 3.66 sellers

http://www.tf2outpost.com/trade/12458653 - 3.66 ref

http://www.tf2outpost.com/trade/11920059 - 3.77 ref 2 weeks (probably lowered his price)

http://www.tf2outpost.com/trade/12157394 - 4 ref 1 week

http://www.tf2outpost.com/trade/12431742 - 3.66 ref

http://www.tf2outpost.com/trade/12243709 - 4 ref 1 week

http://www.tf2outpost.com/trade/12439333 - 3.55 ref

http://www.tf2outpost.com/trade/12360246 - 4 ref 3 days

http://www.tf2outpost.com/trade/12434175 - 3.66 ref

http://www.tf2outpost.com/trade/12415044 - 3.66 ref

http://www.tf2outpost.com/trade/12417405 - 3.66 ref, willing buyer

http://www.tf2outpost.com/trade/12416068 - 3.66 ref sold

http://www.tf2outpost.com/trade/12453006 - 3.33 ref sold

http://www.tf2outpost.com/trade/12440186 - 3 ref sold

http://www.tf2outpost.com/trade/12436289 - 3.33 ref sold

http://www.tf2outpost.com/trade/12418562 - 3.33 ref sold

Below 3.66 sells too fast to include in the price, and it's hard to find.

Easy to obtain for 3.66 ref.