A friend that I shot with years ago made his own weight but without a machine shop that is a bit more difficult. I don't know if they will ship to Canada but you can check if you are interested, DJ Precision,Arlington Heights, IL makes a copy of the original. At $48 they are about 1/3 of what an original would cost from what I have read on American S&W forums.
Damn, T&G beat me to it.