Andy,
I found a very good price ($20.39 + $4.95S&H) on the IR543 X10 controller. Here is the info and link:
Worthington Distribution
Order Line: 1-800-282-8864
[Link: worthdist.com]For the lamp and appliance modules, I found that
[Link: x10.com] sells x10 in Canada. They also list retailers that may have better prices.
x10.com also has many kits with good prices. I don't know if they charge for shipping in Canada.
Good Luck,
Mr. Wizard