I have a kevlar kayak and over the last few years I have managed to put a few good dings into the Gel Coat but I couldn’t find any Gel Coat touch Up kits. I was in a Michaels Craft Store in either Langley or Surrey and bought a 2 oz bottle of “Craft Smart Outdoor Acrylic Paint”. There are many colours to select from and it has worked. I clean the area with alcohol and put three thin coats onto the damaged area. It is not as good as Gel Coat but so far it has worked well.
Hoped this helps.