98 Civic EX Questions

We just picked up a 98 Civic EX for my 17-yr old son last night to
replace the 98 Civic LX he totalled 4 weeks ago (wasn't his fault and
he miraculously didn't get hurt).

Anyway, the remote keyless entry doesn't work which is due to the fact
the factory radio was replaced. I've seen several threads here on
this, so the only solution would be to get a Honda factory radio or get
a new receiver and transmitters a la partsexpress.com's 330-145, right?

Beyond that the power window switches on both rear doors do not
function. The motors are fine as the windows can be raised and lowered
from the driver's door. It doesn't appear to be the lockout switch
either, since when it's locked the passenger front door window won't
operate (as expected) while it does operate when unlocked. Is this
just a matter of bad contacts in the switches in the rear doors, or
should I be looking for something else?

Thanks,

Kevin