I have used NOS wheel cylinders and master cylinders, however, I would always disassemble them, hone the interior, decontaminate, and then using the original rubber parts, reassemble them with brake assembly lube. I did that on my 1963 Chrysler when all I could find were made-in-China wheel cylinders that were garbage. I had the original power brake booster rebuilt by Booster Dewey (check recommended vendor forum for more information). I would have new brake lines made using the newer copper/nickel tubing, and buy replacement hoses from Rock Auto or your local auto parts store. If Karps is still relining brake shoes I would remove the shoes and send them to them for relining. Your original shoes were riveted linings, and Karps has the proper materials available. If you would like NOS brake shoes, I believe that I know where to source them locally. He might even have NOS wheel cylinders. Once all the parts are replaced, fill the system with Silicone brake fluid and you can forget it for the rest of your life. I did this with my 1964 Corvair over 20 years ago and the brakes are as good today as they were 20 years ago. I do inspect them every year, and no leaks or other problems.