Is it at all possible to obtain a Chinese visa whilst travelling abroad?

Hello, I am a Canadian citizen currently vacationing in the Philippines for close to 10 months now ending in December. I have been able to visit a few other surrounding countries, however, China seems to be the only difficult one. I am trying to start off in Shanghai then taking trains to Xi-an - Beijing and moving onwards to Hanoi, Vietnam overland. The PRC embassy in Manila does not give out permits to foreigners and that it is suggested to obtain it in my country of origin even though I have proof of all my hotel/train/flight bookings (no return ticket since I want to travel overland to Vietnam, but I do have a proof of return ticket back to Canada from Manila)

Based on all my research and readings, I found as a Canadian, I am able to travel to Hong Kong with out an entry permit for a maximum of 90 days. So my question is, if I get to HK, how can I go abouts travelling to my other intended destinations? Is there a way of obtaining a tourist L in HK or elsewhere allowing me to safely continue my travels? I clearly can't go back to Canada and back to Hong Kong

Any help is appreciated, my intended departure is for Oct 23/2014 so I have a couple of days to hang out in HK before Shanghai.