There are a few oils out there that have the zddp additives. Lucas hotrod oil was another. About $50 for 5 quarts at Summit IIRC.
@nearpar
Great site for info. In fact they tested the Hot Rod oil back in February with good results
PQIA Test Results in on two motor oils formulated for classic and muscle cars, and one with POE-PAO baseoil | The Petroleum Quality Institute of America