Not many 1980 models were sold. Fortunately, the 1980s models were all pretty much the same (except for decals and the engine beginning with 1982)...unfortunately, they sold so poorly that Honda stopped marketing them in the US after 1982 and in Canada after 1986.
Best places to search for parts are Dratv and CMSNL. The `doc has a good variety of parts that can be used with little or no modification. I believe that the carb is still available in more than on version. Frankly, I'd mothball the original carb and just buy a repop K0 type...far more user-friendly. Take a good look through their electrical parts listings. I've seen a switchgear unit, as you're seeking, that might be close to plug & play (if not truly that) only the finish is silver aluminum. Headlamp reflector assemblies that fit this model are easy enough to source; again, dratv sells these in multiple flavors. As for the plastic chainguard...good luck. Maybe one will pop up on ebay. You can substitute a K0-79 version, those are painted steel. They're also widely available, new.