Sorry I meant easier to find AC/DC Walmarts.
Well I live in France too, and I can confirm that finding a AC/AC power supply is quite a pain in the neck. Do you have a link or reference for the dual DC wall wart supply you’re using? It might be useful to me 
AC/AC supplies are a little harder to find but I aways find what I need in local electronics shops. These things are heavy and bulky and it makes sense to buy them locally. Ask, and if they don’t have exactly what you need, they will likely order it for you from their suppliers. You will be surprised by how many small companies there are that make that kind of stuff and supply locally.