Grouse Guy,
If you post pictures, I'll take them to my Japanese gun dealers to see if they can identify it. It'll take me a while (don't see them very often), but I can see what they know - both have been around the business a long time and know most, if not all of the manufactures in Japan. I'm actually going to see one of them tomorrow, so if you get the pics posted soon, I can take them tomorrow (Wedensday in Japan - Tuesday in the states). The other guy I will see either this weekend or next weekend.