That said, it's a 46 year old cam design and cam tech has come a long way since then. Look for a modern day cam design and get more out of that motor. It what I did in my 340.
I asked Rick Ehrenberg of Mopar Action the same question about the 68 340 4 speed cam and he said go with a modern fast rate cam for more power and streetability instead of a 45 year old grind.
I was looking at the Comp Cams XE268H which is their modern fast ramp rate grind which is the biggest cam possible in the XE line with the factory valve springs.