I have a 68 m725 trying to get it road worthy. In the process of doing the brakes got the rear brakes off and got some questions I tried using the search function but it won't let me type anything in. So here are the questions I jave.

I think the master cylinder is not working is there a replacement or an alternative one to get.

Can I get brake shoes for it. If so what are the part numbers. O read over on steel solider they are hard to come by and can I use gladiator brake shoes.

Also the wheel cylinders need some of those too.
Any help guidance would be freaking awsome.