It does look an awfully lot like the one on my '76 (115 body). Not identical, but close. Best thing might be to take out the valves and diaphragm & match them for size with replacement parts before purchasing. There's nothing high tech here and no "calibration" to speak of (a diaphragm is just a piece of material; valves just bits of steel & plastic), if they fit physically, they'll work. Good luck!