Hi Lara - I have one of these gorgeous machines, too, and I also am leery of the electricals. We haven't tried replacing the wiring yet, but will be doing that this Fall.
You are right about the National Sewing Machine Company manufacturing this machine for Western Electric. Actually they only did it for 2 years, and then Western Elect decided not to sell them. You can find information on needles, bobbins and maybe a manual at the ISMACS website.