Well on ike sound says Kicker C12VR4 Subwoofer 12" Dual 4-ohm Voice Coil Component Subwoofer...
so if Those are yours you can buy a Profile California CA800 $135 on ikesound.com that amp does 600rmsx1 at 4ohms so each sub wired to 8ohms in series and then both in paralell to 4ohms you´ll be receiving full 600rms. I think that the best you can do with $150....