alpine ftw. mine cost like £70ish from ebay. awesome stuff and it came with the kca-420i box for ipod connect. 3 preouts, with dedicated subwoofer and has really good adjustment of frequency, volume of bass, treble, etc. Sound quality is amazing.
of course you can get them new, not sure how much. I would recommend you get one of the CDA-.... headunits
LL