Hi Rick,
I like this one!
As you say above, it is very nice to get the Persian/Omani barrel!
We do not see many of these on jezails or toradors, odd one, but that's it.
It (The barrel) looks well worn, and has had a lot of use, but it is still a grand specimen.
As for lock with replacement parts;
This is to be expected when we think of where it came from and the conditions it 'lived' under. Brass may be later, I don't know, but the decoration to me appeals more than tons of mother-of -pearl!
Are you going to revive and fire it?
...I think I would.....