You may also buy a battery on taobao.com. For example
http://detail.tmall.com/item.htm?spm...156&abbucket=5
As an agent you can use cssbuy.com or mistertao.com. I prefer cssbuy.com. But you should know that better buy battery + another items (for example case ) because there can be troubles with shipping pure batteries.But you should ask agent about all details if you going to buy the battery. There are skype contact on the agent page (cssbuy.com)