Oh cool, that's pretty close to where I live.

If you know your way around and aren't daunted, the best place for car stuff is Banawe St. in Quezon City. Kind of far from Parañaque - 30 minutes' drive going north on a rare good day - but it's worth it. A similar place which is closer to drive is Evangelista St. in Makati (almost at Pasay) but it doesn't have the same ultimate breadth of parts as Banawe.

A word of caution:
Do be careful about parking in Banawe as the less-than-scrupulous can snatch up parts from your car while you're not looking...side mirrors are a common target.