I was looking for one as well, I tried contacting the Norton UK company and after several emails asking for one I got no replies, Havent checked the last few weeks but it wasnt on the website when i looked.
I talked to the guy up in Canada with the 961 Norton and he got one with his bike, but mentioned there is one posted on a website for download and he pointed me to a free download on the net and i slurped it up. Havent had time to read it yet but plan to print mine out and go thru it. The Canadian fellow is quite smart and talented with a LOT of experience wrenching on British machinery, he told me the manual wasnt very good and perhaps written by an office person with no real experience. He felt he had better ways to fix the issues on his bike that have cropped up than they way the factory says to in the manual.
Im open to ideas and have a bit of experience myself (Im a federally licensed aerospace tech) so I am anxious to assess the manual indepth.
But i strongly feel for any bike project the first thing you obtain is a parts manual showing all the bits and a workshop manual of substance. Waste of time without them. Some are better than others.
In my experience the very best manual i have ever used or seen is the factory Honda CB750 manual, and the standard all others are judged by.