When you get around to working on it, SimWorks sells cable housings (made for them in a variety of colors by Nissen in Japan) that are the closest thing I know of for old French and Italian bikes. I install a lot of it at work, and it is very high quality housing, for what it's worth. A box of housing only comes with 4 ferrules though, so it's often worth it to order a few extra if you aren't installing it in a bike shop with a bottle of the same ferrules on hand.
This is a complete reproduction of a steel rounded outer cable which used to be produced between 1950 and around 1970. However, this is not just only a reproduction but including an inner liner adapting a modern usage standard, which didn’t come along with in those days, and pulling a brake...
www.sim.works