Wish I had a good answer for you, but I don't. You didn't say what type of brakes you might want, but if you have, or want discs, it leads to a 'sort-of' problem. I have tried using a master-cylinder from a 66-70 CJ with 11-inch brakes, and also with discs. Works fine for 11-inch, only fair for discs. I once tried to make brackets to put a dual cylinder in... results were ok, but there is not much room. And, one time, I 'remoted' the master-cylinder, and just moved it back to where there is more room. This worked fine, and I was able to install whatever M/C I wanted. As for reservoirs, I sealed-up the cover, and remoted the reservoir, using the plastic reservoir from a foreign car, or from street-rod sources. If I were going to do this again, today, I would check-out street-rod sources, because it is quite common to use floor pedals and disc brakes in early hot-rod chassis, like 30's-type Fords. Wish I could offer you a better answer. Maybe someone else will post a more 'elegant' answer.
bob