A few years ago I bought four volumes of really old looking books that are clearly specification for Imperial Japanese army and navy uniforms from the early Meiji period. They were not cheap at all, but were really cool with nice drawings. I finally got around to scanning at least one volume - the one for navy petty-officers. The above photo is the first page of the images and the date on the book suggests it's from the regulations of Meiji 6th Year (1873). I scanned it into a PDF and you can download it by clicking here. Enjoy!