If you have 2 speakers not working it might be a malfunction of your head unit or integrated Amp if you have one. Speakers on a 2003 should not stop working just like that you might also have bad wires, unless you've had the volume to full blast for the past 6 years then maybe you really did blow them. You can get some Kickers that will give you some bass over your OEM speakers but it wont be drastic change. As for subs you will be going way over your budget because you will need the actual subs, boxes for the subs and an Amp to drive them.Hope this helps.