Also known as Ying xiong ben se, Knight-Errant is a 1973 martial arts movie that includes shots of a Datsun 1600/510 sedan used as a taxi.

No stills, but there are clips on youtube if someone else can make use of this info: http://www.youtube.com/watch?v=oj-KsPh_TP8

If you can make some captures, we could submit them later