Are you wanting an exact color match, or will any color do?

Krylon's H2O paint is probably the safest since it's water based.

However, it's likely most any spray paint will work if you put in on in very thin coats and have the spray can far enough back so most of the solvent has evaporated before it touches the foam. Be sure to try it on a piece of scrap foam first before you spray it on the real thing.