I have found that the paint color NAVAHO WHITE is a very close match to the gel coat on my 1991 22 cruiser. I refinished the door and made a cockpit anchor locker and painted them with industrial enamel tinted to Navaho White.
The paint was Benjamin Moore but that color is standard here in So Cal at all paint stores. Interior paint comes in that color premixed, but exterior paint must be tinted to that color.
