I live on pesos roughly equilavent ~1400 USD (at a blue rate of 7.6) and I will be upgrading now to get a studio (maybe 1 bedroom if lucky) for $700-800 USD a month. ($4.5-5.5k pesos, they usually offer you a rate between the official and the blue) However, if you bring all of the (US) dollars with you, you can negotiate a very good deal, especially if you pay all upfront. This could be dependent on your Spanish abilities.
I could see you paying $700 dollars per month for a decent 1 bedroom if you pay upfront 6 months in USD cash, plus $700 USD deposit (you should get back) Most of these are priced in the $800-$1000 range or more.
Average taxi ride is 50-60 pesos - let's say $1000 pesos a month for 4x per week
Average decent-ish dinner (sit down, with wine) is ~$90-125 pesos - let's say $3000 a month for 6-7x per week (You can order delivery or eat in a regular cheaper place for maybe $50-70, think pizza/milanesa and drink, so maybe this lower it a bit)
An expensive dinner varies based on definition but could be ~$250 pesos - let's say $1000 pesos for 1x per week
Going out for drinks, etc on the weekend is going to run you maybe $300 pesos, depending how you live - $1200 a month
Groceries, toiletries, etc - $200 a week - $800 total
Total living expenses = $7000 pesos @ 7.6 = ~920 USD.
Total expenses = $1620 USD
Note: this assumes you leverage your financial situation and can get a rate of 7.6 to 1, which you can do by bringing in cash and trading it on the black market (up to 10k USD on an airplane undeclared), and you can get a lesser rate on Xoom if Canada has it. Many landlords will also take paypal payments in dollars. This also doesn't take into account 25-30% annual inflation, which, for you, is offset by rising blue dollar.