Sadly probably less than 10K, or maybe somewhere in that neighborhood with the wheels. Green might be about the only thing going for the car because some people desire it, others hate it. The stereo won't add much to the value of the car, your probably better off putting it back to the stock configuration if you sell it.
Sad isn't it? You might be better off trying to sell it locally, eBay doesn't fetch the most money most of the time. People are looking for deals on there. I'd hate to see you go. Is it the engine issues that are making you consider selling it?