That distributor rotor looks to be a 52 series.
It has been used in MANY different cars (American Motors, Chrysler, Jeep, GM, Studebaker). It should be very easy to find, even in France.
PART NUMBERS: Standard Motor Products #DR311, ACDELCO D426R, BWD 138Z, Duralast DR969 and DR-169, Echlin ECH RR1670 (heavy duty one).
Just order a Distributor Rotor for a 1957-1974 small block V8 Chevrolet.
If you are looking for a superior replacement, the MSD 84673 'Race Rotor" is the way to go.
Race Rotor
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