Didn't look too closely at their rim selection, but there were a few bikes there set up with Mavics.
Try emailing them yourself.
ws-giant1@163.com
Urumqi is better stocked. Not only is there a Giant store, but there is a "bike ghetto" that have Shimano, SRAM, Sun Rhyno Lites..... The bike ghetto is located on the Western End of Wuyi Road.
10

sudongpo
11

camel
The Giant shop in Kashgar is OK. Carefull if you have any maintenance done, they seemed to get frazzled easily (and I wasn't looking over there shoulder or anything). Just a tip to re-check any work.
They are however extremely nice, and do go out of there way to help tourists. They can have parts shipped in a few days for you from within China (ie Chengdu or perhaps even Hong Kong). They got me a pair of used clipless shoes from a friend in no time.
Pro tip