I don't know any specific print houses in Vancouver but they do exist. Just have to ask around I guess. Make sure you ask for giclee prints on canvas (pronounced jee clay). That means the print will be particulary good and hopefully look more like the "oil painting" idea you seek instead of a banner or vinyl sign.

A good idea too is to ask about their ink brand. Some printers use lower quality (more economical) inks which haven't been tested so they may not be as fade resistant as you would like.

I live in Victoria BC so Vancouver is very close.