Ok so they are 250 RMS. SVC or DVC?
So you are going to want to probably send them around...~200-250RMS.
Some amps that come to mind would be... :
Kicker 02KX400.1 ~$350
Phoenix Gold QX500.1d ~$380
Rockford Fosgate Power 500bd ~$300
I would also look at the comparable Tsunami, Crossfire, Arc, Autotek, Zapco, MTX, US Amps, US Acoustics, DEI, PPI, and HiFonics respectivley.
- Steve