What's the serial number on it? That might tell who manufactured it.
Otherwise, try to match it up with another Japanese xx machine, like a Brother, or one of these Duluze ZigZags
http://www.sewingmanuals.com/Sewing_...xe_Zig_Zag.htm This has those buttons on the base but maybe one of the others has those two knobs or sliders at the upper right, too.