5-speed campy hub internal rings?

[SalmonDog]

I was feeling some grinding on my 1980-ish novo record group, so opened it up and discovered some parts I don't understand, so I'll try to be as clear as I can:
- take off the outer most ring (has the pinholes for the v-shaped tool, I used a pin punch)
- lift off the gear cluster with outer set of bearings
- at the base of the threaded shaft the outer lock ring was on, about level with the outer bearing race, are three hair- to paper-thin metal rings, stacked on top of each other; the lowest has tabs facing inward that sit in grooves along the inner shaft; one of these rings (the thinnest) had been trashed pretty heavily, came apart into two semi-circles when I lifted it out
other than that there's no damage to any components, and I can't tell what rings so small would do: they don't seem to be bearing race material, and they're too low (I think) to support the gear cluster as an internal spacer.
Is this one ring necessary, and if so is it possible to replace the one? Or is it ok to put it all back together, minus the one hair-thin ring, and expect no difference?
Thanks

(I'll try to get some pictures up later to help clarify)