I don't think there are any after market parts if that is what your asking. But almost any engine of that vintage could be helped a "little" with a more modern ignition/carb/exhaust, but everything would have to be custom hand built ie, carb adapter,custom headers, hand fitting points condencer to that dist, good coil and wires. But in the end there is no way to know what you would really end up with. Perhaps installing a glasspac muffler so at least it sounds that part might be best.

paul