Hey if you are in the ATL area I have a Ample Audio exonic 450. That you can run the subs @ 4 ohms per channel. It is 150X 2 @ 4ohms. @240 x 2 @ 2 OHMS. If local I will do $65 picked If not I will do $65 plus actual shipping which would not be over $10. It is almost virtually flawless.
anyway if you are on a budget, look for amps like kicker zx300.1, alpine350, mtx thunder 421, etc.. just find something that is going to be a solid amp and put out the numbers without spending a lot of money..