Classifieds:

All 5 refined

Solds:

http://www.tf2outpost.com/trade/24078198 - 3.0 refined

http://www.tf2outpost.com/trade/24082434 - 5.0 refined

http://www.tf2outpost.com/trade/24083658 - 7.0 refined

http://www.tf2outpost.com/trade/24083108 - 5.0 refined

http://www.tf2outpost.com/trade/24083951 - 4.0 refined

http://www.tf2outpost.com/trade/24076816 - 7.0 refined

http://www.tf2outpost.com/trade/24077467 - 9.0 refined

http://www.tf2outpost.com/trade/24078198 - 3.0 refined

http://www.tf2outpost.com/trade/24078098 - 8.0 refined

http://bazaar.tf/trade/1142309 - 7.0 refined

http://bazaar.tf/trade/1142509 - 6.66 refined

Sellers:

http://www.tf2outpost.com/trade/24083225 - 5.0 refined

http://www.tf2outpost.com/trade/24083842 - 9.0 refined

http://www.tf2outpost.com/trade/24083934 - 5.0 refined

http://www.tf2outpost.com/trade/24084069 - 5.0 refined

http://www.tf2outpost.com/trade/24076952 - 9.0 refined

http://www.tf2outpost.com/trade/24076967 - 7.0 refined

http://www.tf2outpost.com/trade/24084017 - 6.0 refined

http://www.tf2outpost.com/trade/24078438 - 7.0 refined

http://www.tf2outpost.com/trade/24079543 - 6.0 refined

http://bazaar.tf/trade/1142645 - 5.0 refined

Conclusion

3 refined is a quicksell, so I'm keeping it out of the range, 5 to 7 refined appears to occur most often.