Mike-
If all else fails, just take the sample card and see what matches best.
Zolatone at least used to be a mixture of two different colors and types of paint, stirred into a marbelized mixture in a pressure pot, then sprayed under low pressure onto the object, resulting in a splattered and textured surface.
Depending on how much you stirred it , and how much pressure was used, it always came out different, and would be difficult to match.
The environmental laws may well have changed the formulation of Zolatone; I doubt it's composed of an enamel and a lacquer, for sure.
The question would be whether it could be matched and how well. Talk to a professional paint store about this question and what equipment you'd need to apply it.
Another alternative is a recent product development by (I believe) Rustoleum, which is a splattered and textured surface intended for outdoor patio furniture. It comes spray cans and in colors similar to Zolatone, and I've used it to match Zolatone very well. It can be "feathered" or "fogged" in at the edges of the repair very nicely, too.
The only limitation is the fact that it's softer than the original Zolatone, and they recommend spraying it with a protective clear coat if it's going to be left outdoors continuously, which would complicate the repair.
That's as much as I know at this point. Don't be afraid to call the Zolatone Customer Service number and talk to the Technical Representative to get further advice as well as the one at Rustoleum.
Good Luck!
Joe. :teeth :thup