Hi, Jack --
There should be a Dahon shop in Guangzhou at this address: Huanshi East Road Number 447, Unit 101. I don't have a phone number, unfortunately. You should expect to pay aboutRMB3300, or USD425, for a Speed P8.

东山雅航百货经营部
广州市环市东路447号101房

From this site: http://www.dahon.com.cn/buy/proshop.htm