I've had good luck by calling Spectrum. I was lucky in that I had the original sales paperwork for my boat and knew the color name, but Spectrum can help you get the right color.
I agree with Mike that a perfect match is unlikely on a 10 year old boat. The quality of the repair will depend on how many steps you are willing to do, i.e. wet sand, heavy compound, light compound, polish, and wax. There are compounds made specifically for gel coat. A level repair and wax shine will make the scratches much less visible.
A scratch that disappears when it gets we can usually be buffed out without adding touch up paint.
2006 Bayliner BR205
A1 Gen 2 1.47
5.0 carb engine