Your frame still has the brazed on bracket for the rear brake cable stop, whereas my 1973 TdF was shipped withe MAFAC hanger on the seat binder bolt, so pre-1973.
You also have the long-point lugs rather than the short-point Bocama the latest foil-era TdF's had.
My 1973:


Overdue for a refresh...


Member Hummer posted a thread to decode the Gitane serial number on the NDS RDO:
Gitane serial numbers