Anything from 1973 or newer is a good swap. That '74 B body car would be fine but even better would be something with 11.75 rotors such as a '76 or newer B body.

You'll have to be careful with caliper location and hose routing. There are lots of parts that will work so don't settle for some hacked together solution just because they were the first calipers or hoses that you found.