Offenhauser camshaft

I'm not sure where to start but I'll give it a try.
I'm looking for a Offenhauser camshaft for 1964 and 1965 273 cu. They were offered for the 1965 season. I dont know if there were different models but I asume it was for drag race use.
I prefer a NOS one but a used one would be ok too. At the same time I would like to find a 1965 Offenhauser catalog so I can see what they offered.

Thanks in advance for any help.