Respectfully, I must disagree with 63rickert's assertion that Gitanes never showed more than basic competence.
Have a look at this
Gitane's seat stay caps and compare them with the OP's.
Unfortunately, the majority of TdFs and Super Corsas I have seen came from the period when Gitane simply swaged the seat stay caps. Later in the 70s they came back with an emblem stamped into them to make them distinctive.
EDIT: Look at this
B. Carre-built frame and its seat stay caps. The shape on these and the other Carre seat stay ends I see online look like they are slightly more diamond-shaped, less rounded than the Gitanes. Maybe it's just my eyes ....