MR2 MK1 '85 Speaker Questions

I'm looking to get some new front speakers and an mp3/cd player for my '85 mr2. I'm also going to replace the box speakers that the previous owner of the car had installed behind the seats ($20 at Wal-Mart). I don't know anything about these things, however. I've spent time looking up stuff on the internet but it's not really helping and so I was wondering if anyone out there had some recommendations. Anything that's not ridiculously priced.