I've found this one->
JL Audio 8W1v2-4 Subwoofers
it says that its rated at 35w-150w rms, and I'm hoping to use the factory amp to power it(in another thread a guy is using factory amp to power a 4ohm 350w rms sub, and says it sounds good and is doing ok). Does anyone know what ohm sub would be better, an 8ohm or a 4ohm? Thanks.