It's a "clone" of the Singer 15, probably Japanese and from the early 50's. :)
Jenny at sew-classic.com carries the replacement parts - I would replace the motor, foot control and cords - you can also get some TriFlo liquid, good quality metal bobbins, spool pins, (she has both tap-in and screw-in types) a bobbin cover plate and some spool felts. I like the spool pins that have holes in the top - that way, I can use my cone thread on a stand and thread the machine through the hole in the spool pin instead of taping a darning needle or safety pin to the machine. :)