you can get components for the front but you'd have to mount the tweeters in the tweeter pods yourself.
good luck.
Oh and replacing six means all the woofers and leaving the front tweeters alone. that can be done.
Just find something that fits your budget or dare i say go to a sound board and take a listen. Note that will not be at ALL what your car will sound like with those speakers.
all speakers will require proper amps if they're decent speakers and you actually like to listen loudly.
If not, then any deck will be fine.
They're all rated for 14 W RMS at 4 channels anyways.
