[SkipB]

428,

You might try a couple of products from Dominion Sure Seal. Both in an aerosol can.

1. Rubberized Undercoat (high build) #SUR
2. Aerosol Bedliner #SEZL

Buy a can of both, spray on some scrap and see what gives you the build/texture you want.

Should be available at automotive paint stores.

SkipB