There are choices
I'm planning to re-paint my deck also. PO painted over the non-skid patches, but I've found 3 choices.
1. You can buy non-skip material, either bulk or pre-cut for your vessel. I assume it gets glued into place. A bit pricey.
2. Non-skip paint, made for marine applications. Also pricey per gallon, but I would think 1 gallon would suffice in most cases.
3. Non-skid additive. This is the most cost effective, add it to whatever color paint you want.