Jim, if the tabs were on the studs, then belts were never dealer installed. I suspect the tabs were removed by a subsequent owner, but it is interesting to see you found the tabs. I doubt if you will find factory belts, but good hunting and good luck with #183. Enjoy. Another thought, if you do find the original belts, I don't think they would be safe to use. Like tires, the belts would have a lifespan that has expired. They would be usefull patterns for new belts. There are companies that can remake belts from the original patterns.