7-Eleven is a good option. Another good option is Petro Canada Mobility prepaid phone. 20c/m for local, 30c for anywhere in North America, caller ID included. If you buy $20 credit, it will be valid for 180 days, and will be carried over if you refill it before it expires.
Petro Canada Mobility is over Roger's network, so the coverage is good, and the phone is not locked (you can use it for other GSM provider).