I would go with the highest capacity ESC I could afford. That way if you do eventually have the funds to buy a hotter motor you won't be replacing your ESC as well. My foamy setup is as follows... Himaxx 2015-4100, GWS D ratio gear box, Castle Creations Phoenix 25 amp speed control, Kokam 1500mah 11.1volt pack, Hitec electron receiver and 4 HS 55 servos. That may be a little pricey for your needs but I shopped around and was right in the 250.00 range when all was said and done. Of course that's not counting a charger. I've got a Triton but there are cheaper ones out there. You're already cutting some dollars off what I spent because of the price of the motor you chose and you won't need but 3 servos. I'm assuming you are going to run a single aileron servo with a 4 channel radio of course.
BTW there are some great deals out there on motor/esc combos if you look. I like to deal with www.allerc.com myself but there are plenty of others.