It uses CDMA and AMPS, not GSM. Nor for Telus. See the countries page, you can get Rogers, or Fido and pay the $5 fee to include the Rogers network, but good luck in Nothern Ontario.

You can also buy a bell prepaid phone. You can also buy somebody's used bell mobility phone and try to activate it, but that may not be that much better a deal, surprisingly. As somebody suggested, you might find a prepaid phone for sale in a hostel.