I am a Canadian citizen currently traveling in Cambodia, with plans to be in Vietnam in a few weeks. I am hoping to obtain a visa to travel through China en route to Mongolia, spending less than a week in total in China. As a temporary visitor, is it possible to get a transfer visa (7 days or less) at the Chinese consulate in either Phnom Phen or Ho Chi Minh City, and if so, how long does it typically take to process the application? Thank-you for your help.