subs for my '00 RS sedan

Hey, im trying to decide what kind of subs to get. I am on a budget so i cant go all out and spend 600$ on subs, but i know there are good deals out there. If anyone has any good suggestions on what kind of subs or if i should get 1 12' or 2 10's it would be greatly appreciated.

I have 1 10. It's more than enough for great sound quality, and this is coming from someone who used to have a 3 sub 2000 watt system in my old car.