not in Mississauga but close enough, used them for all my SS bolts for my bike restores, they might or might not have fine thread in stock
http://www.pacificfasteners.com/
and nicely packaged....
I would go to any bolts plus location, they have always been more than accomadating. They also carry fine metric.
Ask for the PAFCO catalogue.
bolt/nut supply houses are always min. purchases. they supply to industry not to someone needing 3 bolts and 2 lockwashers. hardware stores such as lowes/home depot/homehardware/tsc/ctc have alot of selection.