K.F.C. 12 ga. SxS

I just aquired a Kawaguchiya Firearms Company double barrel, 12 ga. side-by-side shotgun. I found K.F.C. listed in the Blue Book, but nothing on a SxS. This particular gun has amazing detailed scrolling engraving...even the screwheads are detailed! It has Kawaguchiya Tokyo on top between the barrels, and Hibiki Co. on the sides. It has a 4 digit serial # 30XX, and when you break it down it is stamped again with the serial #, along with 1955...possibly the mfg. date? It has a unique safety, located on the left side of the stock. The closest think I have been able to find on the internet is a picture on the link below as "No. 19". almost at the bottom of the page. Anyone have any info on this? I can take some pictures of it.

http://members.shaw.ca/tju/muratashotgunpix.htm