Your best bet will be find a donor(Craigslist or other vintage parts site) or fleabay. The CDI is pretty specific to certain models so you will want the right parts or as close to it as feasible. A voltage regulator shouldn't be too hard to come by and that you can retrofit from another brand/model if necessary. Plug wires can be bought or made and depending on the coil set-up they may come with it. This site is slower than slow so unfortunately you may find better help elsewhere.