you should be good with just a remote for a civic of those years off ebay or wherever
they can all be programmed to your car just fine
the 1996-98 civic lx and ex have it in their radios, they changed it for the next models
i have a 1997 ex and bought a remote of ebay, it worked fine until i fried my radio, my own fault, so i am pretty sure you should be fine
good luck