i dont the rating is per coil, usually the rting is for the sub as a whole.

lower impedance doesnt give the sub more power, but it double the power of the amp.

u need to look for amp that corresponds to the power of the sub, at the impedance from the wiring.

if the sub is 350w and u plan to wire it parallel, u need a 175W amp, which gives 350W at 2ohm

i guess can look for amp that gives 350W at 4ohm or more, shouldnt be that hard, i think got quite a few 400-500W amps in market

yea so look for an amp that can go 2ohm with rms power same as or more than the sub's rms power