Re-grinding a cam, educate me please

Good morning FABO.. I want to build my 340 to 1968 4-speed specs, Rusty has me very interested to call Oregon cam and order that very cam. Here is where im confused on re-grinding an old cam to new specs, how do they do that?
AM i better off ordering a new cam from Oregon or can they re-grind my old cams that i have in the attic, one is a 69 and one is a 70 cam, I keep hearing that the old metal is superior to the metal that they use today. obviously im not educated and im hoping FABO can help me out. I will also need lifter recommendation... any help or advice is always appreciated...Rich...@rustyratrod