That rear axle is from a 1955-64 passenger car. If the housing is set up for leaf springs, it would be from a 1955-57 year vehicle. 58-64 cars ran coil springs and a different set of axle tubes on a center section with the same bolt pattern for the carrier housing to bolt into. The most recently manufactured versions of that rear end will be 60+ years old, and aftermarket gears and rebuilding parts are anywhere from scarce to nonexistent. It will also have a 5 lug wheel bolt pattern, different from the 6 lug hubs on the front end.
Jerry
Are you saying I’ll have a hard time finding pinion/axle seals for this rear end? I can make the gasket