The service manual durations are based on the ramp geometry in engineering drawings, not the SAE or other common standards. You can do a search for @Wyrmrider and maybe a key word like 'drawings'.
Oregon's '68 4-speed cam may be about as close as can be easily purchased.
There was someone who was going to reproduce it more precisely if there were enough participants but the ignorant hecklers drove him off. :(
Later in the same thread I show the simulated hp curves assuming incorrectly the service manual specs were .006, and then correcting as much as the program would allow using .004 from some of the catalogs.