OK, big, you got it...have a break!
I never owned a (later edition) TdF with these features (Sugino cranks and Campy Nuovo GS hubs, etc.) so wasn't aware of exactly which things were stock. Mine was from the early times (~1970) when the TdF was "supposed" to be the "all French" model: there were no Japanese or Italian interlopers allowed. I never had any issues with replacing the French components with Japanese or Italian when those items broke, I even replaced the Mafac RACERS with other brakes and they were not broken (just annoying).

The reason we know the Simplex RD will go is precisely because it's about 40 years old and made of Delrin. It's at the end of lifespan, now just a matter of time.

My comments were meant to inspire the OP to not be afraid to use new rims (I think the VOs and Suns are both good choices) and SS spokes since those will do no harm to the value of his TdF and will only increase its practicality and his enjoyment of it.
Same for the RD: Gitane was not ashamed to eventually spec Sugino cranks as original equipment; in that spirit thousands of owners have tapped the (Simplex) RD hanger and used a Sun Tour V or Shimano Crane...knowing what I do now I'd look for a Simplex 600 series RD and skip the tapping (for a while)...once that Simplex Prestige breaks, of course, no reason to be proactive...