That tire size will be written on most current relevant tires as 650Bx35. The ISO designation for the same size is 35 - 584 (it's another way of saying exactly the same thing as 650B x 35, and some tire manufacturer sites use the ISO number.) The exact width match (the 35mm part) can be fudged a little if needed depending on whether a bigger tire can fit in the frame/fork/fender. Today you can find 35mm wide 650B tires, but there are more options starting at the 37 - 584 size. Panaracer, Continental, and Schwalbe all make utilitarian tires in that size that are at home on old French city bikes etc.
For tubes, most tube manufacturers now have a size in their line that's labelled as a proper 650B tube, i.e. you can buy one that just says 650Bx35-42 or whatever on it. 650B tires take 26" (559) tubes without issue and some manufacturers (Schwalbe) still have the same tube box say both 26x1.5" and 650Bx38, for example. In other words, if what you come up with is a tube box that says 26x1.25-1.75" or the like, that will work fine.