Choosing a replacement diff housing

I had a D series Ford that had a hand brake set up that looked a little along those lines
So maybe the mechanical linkage is a lot more common than you think as the D series was at a guess mid 70's
Still had a slow diff but that never really mattered back in the day as the speed limit in most part of Australia then was still on 80 kmh for trucks

Paul

So I cleaned off a bit of dirt and rust and dried up grease from the diff and found an old repair that has been done at some stage in its life.
i.imgur.com/t1yXSwc.jpg
i.imgur.com/wHBU8tx.jpg
i.imgur.com/dKxQZ0O.jpg
i.imgur.com/aZ5NkQK.jpg
i.imgur.com/353Lu6R.jpg
i.imgur.com/EaZs8TG.jpg
i.imgur.com/FvUtTUJ.jpg

My question is would this repair be safe for on road use? Or would it be a repair done to keep a farm truck rolling around the farm?

IMO "If it aint broke, don't fix it."

It looks like a really rough casting, rather than a repair. I'd pull the guts out and see if there is any sign of a repair on the inside.