For sulfuric acid in Canada you can go to specialty battery stores like Total Battery, you can also go to automotive stores that only sell auto parts. Places like Autozone, or Automotive source.
Call around, the automotive places will be much cheaper than the battery places.
A battery place will charge $45.00 Canadian for a cube (20L)
but the automotive places usually charge $21.00 Canadian.
Places like Canadian Tire will not sell acid.
You can also try Canadawide Scientific. You can buy 98% sulfuric Lab grade acid there, but it costs approx. $70.00 for a 2L jug