You can go to yahoo groups and join the group vintagejapansewingmachines. Once you have been accepted, you can click on their files section and then go through the different manuals and see which one looks most like your machine. They're pretty similar but may not be exact. I think if you download the Dressmaker SWA-2000 manual, it will look a lot like your machine. The difference would be that the 2000 will accept design cams in a door on the top and yours probably does not. Otherwise, it should work for you. Also look for a generic zigzag manual there.
Good luck.
John