50s or 60s product advertising music?

You've defined it. What help do you need? If you search for a particular product and "theme music" or "commercial", you'll get appropriate hits. Also, what cartoons do you mean? The ones I watched didn't advertise products, although there were animated commercial ads. Jingles were far more common than simple sound effects. Do you have a particular product in mind, or is it specifically the pizzicato effect you wanted?