I know on the newer machines we would measure them as there is a spec size and re use if a few marks and no deep scratches or heated areas, if some dis colour we would put back in anything outside of these we would go new, generally aftermarket or OEM (if no stock), with older machine I have no idea, im sure someone will chime in to get it correct for you, Cheers
It is a balancing act, between your wallet, and your ambition, amount of expected use.
There is spec for minimum and maximum height of the stack of clutch plates. Cat only talks of adding one extra of each plate. In lean times I have added more old plates. At that point the inner and outer drive teeth become a big part of if the plates are usable. You are not taking a chance of causing more damage if the plates fail. Your just sitting and not turning or moving with any amount power. There are also spec for the springs as well. The only failure of springs I have encountered, they were way less than spec. So kind of surprising it went as far as it did. So if you have more ambition than money you can take some chances on steering clutch plates, that would be foolhardy with bearing or gears.