I seldom travel far anymore, and have not been to France....but my recommendation to anyone traveling anywhere would be -
buy what you need in the U.S. and take it with you if possible. I would not want to rely on trying to
buy much of anything, especially
vaping supplies/ecigarettes in a foreign land.
I would google the locations you will be visiting, and see if you can find the local regulations regarding e-cigarettes. They are actually banned in some countries. Some places allow you to use them, but not to purchase them, so check it out ahead of time.