When on the Singer site, when it asks for model number try just putting in a W. A whole long list of manuals will show up. It may take you a while to find one that works for you.
Many of the Japanese made machines don't have real Model numbers - you just have to find a machine that looks like yours and chances are the manual will work - or ask a friend to help figure it out. Usually not too hard to do, with basic sewing machine knowledge.
Ethel