From the family of the first owner... bought in France... or so the story goes... I've got this beautiful Gitane.
It's like made to measure for me and I'm fairly certain it is the Olympic model of my birth year 1975. Bingo.
I want to achieve two things:
A. double check that my research to this point is correct; and
B. get some specs on the few non-original items on the bike so I'll be able to make it perfect.

It doesn't have the willow leaf that was introduced in 1976 and the NR rear derailleur is stamped 75. Between those two a 1975 model appears highly likely.
The model is the Olympic with all Campa NR minus the brakes, which are MAFAC.
I've got a French poster for the 1975 year which has a Super Olympic and an Olympic Record (that former with MAFAC brakes, the latter all NR incl brakes).
But I think I have read elsewhere that the models were Olympic and Super Olympic (the latter all NR incl bakes).

The non-original items on the bike are the wheels, the brake callipers (got the MAFAC levers still on) and probably the saddle.

For wheels I assume I'll want to look for Campag high flange hubs with Mavic Monthlery extra legere rims?
For brake callipers the MAFAC 2000?
For a saddle an Ideale? And which one?

Apologies for involving higher authorities directly and shamelessly @verktyg