There's Beaver Buzz. I've found it here and there (London Drugs is one place). I wish they had a sugar-free option and were priced a little cheaper, but I don't think I'll be buying Monster any more.
Actually, I just looked into it a little more - they've got it at Superstore. Currently on sale, too. I just wonder why Beaver Buzz has no mention of having anything to do with Canada (it's BC owned and produced) while they've got "prepared in Canada" for Monster and Reign.