Machodoc
Old Guy
Beautiful Nambu rig!!! I agree holster looks good - may even be the original one issued with your gun...I can see what looks to be a "六" stamped on the inside lid (kanji for "6") and if I had to guess I bet that's part of a faded "十六 昭" stamp for Showa 16, same as your Nambu.
Here's a better look at the markings that are visible inside the holster flap. What do you think?