The frame was definitely built in January 1984 by a Japanese company, H. Tano. I don't see how your S/N doesn't exactly match the N(1) format listed for Novara in my guide? Regardless, the Tano connection comes from a 2011 article wherein Geogena Terry lamented that her sales plummeted after her Japanese contractor. H. Tano. started manufacturing identical proportional designs for WSI under their Centurion brand. The serial numbers that I've collected for the Centurion Ironman Proportional and Centurion LeMans Proportional models use the same N(1) format as found on your frame, so it would appear to be Tano manufacture. I consider the article to be strong and reliable evidence, so have been considering changing this format in my guide from N(1) to Tano.