ok heres what i want to do

im gonna get two Alpine type r 10/12 inch subs they have 1500watts/500RMS watss. I plan to get an amp that can peak at 600-700RMS

The question i need answered is.... Will i have to change my alternator to be able to support this system? My car is a stock 98 civic ex, no electrical modifications. If i have to replace the alternator what should i get and where can i get one.

need as much advise as possible cuz i will be buying the system soon.