I Need Help

I have a pair of Gallo 3.1 speakers. There bass recreation is fine to me but they say for optimum bass recreation you shold use their SA 3 amp. The problem is I don't have the $700 on hand for their amp. Is there another amp in the $250 range or lower I can substitute for a Gallo SA 3 amp?
Any stereo amp (150 watts/ch. or more) will work, but you need to filter the signal so that the 2nd voice coil gets only the low bass frequencies. You'll need a crossover device to do this...