Barrells, Miroku Firearms MFG Co Kochi Japan, BNP 12 23/4 31/4 tons per square inch, Special Steel 12GA 23/4 77*** it also has an I in a circle of several hashed lines, sp in a circle with 3leafed flower and the letters NP ( I assume most of this is proof type , but unclear if symbols are proof related or not)

But Pad - BC Miroku

Under the lever - 2277*** (no letters, Im told this may be relevant)

Other than that its got 28 inch barrels, its fixed choke don't know what but obviously different. Single selectable trigger, barrels blued, other metal work silver. Will take some pics in due course. Haven't posted full numbers as didn't seem entirely sensible.

Any help greatly appreciated.