VE OSF Door Lock Not Latching

[Citroënbender]

Odd one here, asking for a friend (who made it my problem this afternoon)!

Door won’t latch, I removed the mechanism to eliminate cable issues etc, can’t make it latch in my hand. It feels like the quadrant pawl is not engaging. No signs of breakage inside the cover, or forced entry attempts.

Is the rear lock interchangeable (it would be cheaper as a used part)? Is it something where you only go genuine? I note it’s made in Mexico, so presume there’s a cross to some US vehicle.

Advice appreciated, thanks.