I use that same kind of lye. I also am from Canada.
It works great! and the guy's at the hardware store never gave me any problems about buying it (I said my girlfriend was making soap).
They did say that it is becoming harder for them to order it because they have to order it in large cases now instead of just a few containers at a time and they are not allowed to sell it in small containers, just the big 3kg ones. It is not a big seller for them so they were not sure if they would bother restocking it.
One other thing. I had to go to 4 different HomeHardwares before I found one with it, so call ahead to see if the store you are going to has it in stock.
Give the spice a little smile... and cross the veil in style.