You used to be able to buy Parker gelcoat from Cecil Marine, but I just checked and they do not have it at the moment (or I missed it). I've color matched, and it's OK...you can get really close, but the Parker stuff just blends right in. Either way, the fix is easy, and like others said, do not delay. Get a rotary tool or manually sand with paper and make the hard edges slowly slope out to undamaged gelcoat. If the area is the size of a dime I'd probably end up with an area at least the size of a half dollar. Clean the area well with acetone, then apply gel coat. Apply liberally and use a plastic scraper to smooth out any of the flat sides (but dont press down too hard, youll want to leave a little extra so that you dont have to do it twice). You'll have to manually do the curve unless someone else speaks up with a tip. Don't worry if you get too much, you can fix anything with more sand paper. Finish with a fine sander paper and then wax it. It's worth calling Cecil Marine or Parker and asking where you can get the exact gelcoat..it makes the final product almost perfect and takes out a lot of the work.