Liquor store at Cambie and 41st Ave.... largest store in the lower mainland.
The best one I've tried to date that's available in Vancouver is Wind Water Man (the characters anyway) I don't remember if the english translation is on the bottle... it might. It's a bluish green bottle.
Also Mizu Aioki is pretty good too. (Haven't seen this one that much recently though). This one is in a transluscent blue bottle.
These are all premium sakes. Should be kept in the freezer for a while and had ice cold like a nice bottle of Grey Goose =)