If you keep the factory deck, you are pretty much stuck with the factory speakers / amps. However, if you get the system working properly, it will actually sound quite decent for a factory system. The original (4.5") speakers actually cover most of the (audible) frequency band, plus they are port-tuned around 60hz...so in reality they have more "body" that most 6.5" speakers do.
I sell used amps for $15-20 each. I can also get new Bose amps, but that can get pretty pricey. As a rule this runs along the lines of $450, even at my cost, but I do get quite a few people that go this route, believe it or not. I have to guess they look at it as an investment that will net 10+ years of a trouble free OE system. Anyway, just email me direct for quicker replies:
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