Check Travelocity regularly as a quick way to check many different companies. I just did this for one week starting June 7, and Enterprise has $218 total for a standard car. Not great, but good enough to book it and keep looking for something better. This was with no special codes, so perhaps it could be lowered a bit...
Expedia.ca is $108 Dollar or $138 Budget inc taxes for standard. Budget includes additional driver Dollar charges $10/day extra.