Not a lot of choice. You can get a SpeakOut or PetroCanada SIM for $10, load some money into it and get what they call "Unlimited Mobile Browsing" for $10/month. UMB lets you browse, e-mail and a few other things but it's not unrestricted data. So VoIP won't work for example. (You get around most of that with a proxy or VPN...)
But my reference to Canadian carriers and foreign roaming fees was intended to make Doodad's pricing look good. See e.g.
Dad gets $22,000 data roaming 'shock' from Fido and
Dad talks $22,000 cellphone roaming charge down to $200
These sorts of charges aren't unusual when Canadians take their carrier-locked phones outside Canada.