use your amazon money and get a kicker zx750.1 solid amp and you will get yo use up the amazon gift certificates. then pick up a dual 2 incriminator audio lethal injection 15. should cost a little over 400 this will leave money to buy the wood to build a good ported box for it 3.5cu tuned to 35hz 50sqin of port area. this will get insane output compared to what you have and be very reliable
