Not sure how similar your system is to mine in my '67 C50, but I had to do a bit of research to find all the parts, and then I had to do a TON of research to find 'em for the best price. I finished the brakes about two months ago after many many weeks of work, waiting, work, and reassembly.
Here's where I started:
http://www.raybestosbrakes.com/magno...=Medium%20Duty
A word from the wise: expect NOTHING to be in useable condition. Thoroughly inspect EVERYTHING before calling off further work on the brake system.
...those damn rear drums are heavy sombiches