Sellers

http://www.tf2outpost.com/trade/20976136 - 8.11 ref

http://www.tf2outpost.com/trade/20915653 - 7 ref painted gold + 7 ref for painted pink...

http://www.tf2outpost.com/trade/20953819 - 7.33 ref

http://www.tf2outpost.com/trade/20761042 - 8 ref

http://www.tf2outpost.com/trade/20979494 - 6.66 ref

http://www.tf2outpost.com/trade/20066791 - 7.66 ref

http://www.tf2outpost.com/trade/20967151 - 7 ref

http://www.tf2outpost.com/trade/20789311 - 8 ref

Unsold at 1 key

http://www.tf2outpost.com/trade/20437914 - 2 weeks, bumped 15 mins ago

http://www.tf2outpost.com/trade/20778143 - 6 days, bumped 30 mins ago

http://www.tf2outpost.com/trade/20779749 - 6 days, bumped 1 hour ago

http://www.tf2outpost.com/trade/20746771 - 1 week (painted gold), bumped 8 minutes ago

http://www.tf2outpost.com/trade/20921869 - 2 days, bumped 22 minutes ago

Classifieds

http://backpack.tf/classifieds/?item=Ball-Kicking%20Boots&quality=6&tradable=1&craftable=1

-1 for 6.66 ref (painted orange)

- 1 for 7 ref

- 1 for 7.22 ref

- 1 for 7.33 ref

- 1 for 7.66 ref

Overall, this item is quite hard to sell for the current price, and i feel that 7-8 ref is a more suitable range as most sellers are willing to sell within that range.