Or......just spray some rattle can enamel over the areas? Something thats non-porous to not let moisture thru.
On a slightly different note,I just had some paint matched and put in a rattle can so i could paint my visor to match the truck. It worked sweeter than honey!!!
Got the exact match.
Dont have to fool with mixing paint,catalyst,reducer,etc.
And I always have the paint ready to go when I am.
Marty