There's a mainstream interest in Japanese derived minimalist art and architecture, zen buddhism, the same for antiques of the right kind, but I doubt an old sewing machine will get you there. Swords and prewar Japanese items will fetch money and a dealer in them will fetch interest world wide. Post war Japan sort of climbed up the ladder and with the 1980s their ecomomic miracle happened. These days technology and computerized gadgets have taken the front seat. Not sure where the miracle is right now, but I doubt it's remnants of the world war occupation. Any interest will lead towards something though, it starts with small things. A sewing machine is mostly for the person who use it.