Beijing Needs Gas Pipe for Mallet Heads!

I'm trying to help the Beijingers get some bicycle polo going, but we're having a hell of a time finding HDPE pipe. Ironically, much of the pipe we use in the US (and everywhere else for that matter) is manufactured in China. But actually buying pipe in Beijing appears to be nearly impossible.

Construction sites are locked tight--and often patrolled by guards. Building supply stores--and there are thousands of them--are often little hole in the wall places all carrying the same products. Heaps of PVC, but not a meter of HDPE/ABS.

I went to the Home Depot yesterday (Chinese Home Depot=irony) and they had 47 brand new kitchen sets but not an inch of gas pipe.

Any ideas about other kinds of materials that might be more common? Or perhaps someone knows about a Beijing Gas Pipe supply store!

Any and all suggestions are greatly appreciated--thanks!