I too am looking for an aftermarket parts/service shop in Toronto (east preferred), one that has actually worked on a Mazda, and stocks some Mazda parts. Usually it's more like "Mazda, yea, I've heard of them...let me check the parts catalogue..."
I stumbled across a shop in Markham, on Dennison, 'Option JDM or something like that ....' Probably, more Honda related. They had lots of Hid and suspension parts around, not sure if Mazda though. The counter guy seemed pretty knowledgeable. Worth a shot.