This is something that came through my dad's gunsmithing shop. He brought it to me hoping I could open it.
https://i.imgur.com/qeARMEB.jpg
https://i.imgur.com/rhWhQfw.jpg
https://i.imgur.com/MZuJQk0.jpg
I had a hard time getting a clear picture of the case lock, but it looks like it's the same lock as the gun itself. I think it's a tubular lock with 4 pins? Never heard of anything quite like that before, but there it is. Besides the one on the carrying case, the one on the gun is a rather unusual thing. It actually goes up in place of the magazine and holds everything shut.
I'd love to have a closer look at it, but sadly I have no tubular pick to even attempt it. Plus I'm rather wary of messing around since we don't know if it's loaded, or if it even could be with the lock on. Thought I'd show you folks just for fun though.