An epoxy filler that is compatible with whatever the hatch material is . For small repairs such as this I would use PC-11 epoxy. It cures to a light blueish/gray, (I'm partially color blind, so take that for whatever its worth) It can also be tinted with dyes, for a close match. It takes about 24 hrs. for full cure, and then can be sanded or machined to whatever profile you like