don't limit yourself to infinity, jl, rockford, etc unless you aren't concerned with $$. you can do just as well or better with a brand you may not know yet:
tru
arc audio
pheonix gold
orion
old soundstream
zapco
search the forums at
http://forum.elitecaraudio.com/ if you want more resources/opinions.
as far as power/# of amps, get one amp (stable to 2 ohm) and wire your two SVC subs in parallel for a 2 ohm load.