consider something from Hifonics. I have the Bxi1606 mono model and it does the job great. lots of power and great sound quality. I think I paid just over 250 for it w/o shippin so its kinda in ur price range. I got it from onlinecarstereo.com, and they sell many different kinds.
It puts out......
@4 Ohm - 550 watts - (my setup)
@2 Ohm - 1000 watts
@1 Ohm - 1600 watts
In my opinion it was a great deal, and if you buy now, I think there is free shipping. Check it out. Worth a look.
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Do your worst for I will do mine