Yes, It looks like it's a Norton Dolls head gearbox. They were used from about 1934 to 1945. The gear ratio on the gearbox 1, 1.1, 1.33, 2.33 matches that used on the Norton International's with kick start. But the gearboxes used on the Norton would have used the the top outer cover with the Norton logo, and your gearbox was probably supplied to another motorcycle manufacturer. It could be from a Brough Superior as they used Norton Dolls head gearboxes in the late 1930's.
