Thank you very much for your answer
I reposted my question because I thought that you haven't seen it. No problem.
You're right, this bag is difficult to authenticate because of the "Made in France" black label. Vintage Dior logo bags usually have "made in france / garanti scotchgard" or "Christian Dior bagages" labels.
But I think this one is an older version of Christian Dior bags, maybe from the late 1950s - early 1960s, and the styles as changed throughout the years. The inside of this bag is not the same as the most popular Dior logo bags from the 1980s. It is more simple, with a long line of canvas on the back of the bag. However, the outside is exactly the same.
It's not the first bag I've seen with this design. I read on internet that the first Christian Dior bags used to have the "Made in France" black label. In the 1950s, the stamps and the logos where less important than today.
What do you think about that?
(Sorry for my english, I'm french).