Alexander, I am of no help in France but we made our own replacements without too much trouble.

We made a template.from large wrapping paper then bought a "remnant" piece from a big-box store. 

Cutting it with a box cutter was not too hard, just have to be careful.

Once we had the pieces cut out we took them to a real "Carpeting and Flooring" store and asked them to "Bind" the edges which they did nicely in only a couple of days.

We learned that the "Binding" process adds a small amount of extra material to the edges so our pieces were just a tiny bit too big but still fit ok. 

I think we will do it again this summer as the first attempt was mostly an experiment anyway.  It was not very expensive overall. 

Best wishes!

Gary W
SM 209, Adagio
Georgia, USA