Unless you're going on the alaskan hwy, bulbs and fuses are common items.
and most of those pesky electrical items can be bypassed. safeties, decomp controller, kickstand relay (WTF does that do anyway?)
Key items that would cause great concern for replacement, TDI, coil, stator, starter relay, and rectumfryer.
The TDI for us comes in 2 varieties, pre and post '88 (gonna have to check transition year) Other than timing (location of the sensor trigger) advance curves are more or less the same and done electronically per rpm. I would think any single TDI and matching coil would serve as a replacement. Of course there could be an issue with timing, so having a commensurate year may work. As to whether you could replace 1 coil with another, probably. Find 1 with the same size, resistance it may work. Please remember that our coil will burn out the TDI if left on over night. So I'd check the amperage of the coil as well. These values may have to be checked by others so that we have values to check against. Checking a burnt out coil ain't gonna work.
stator/rectumfryer, we already know a few models have a similar stator, although the wiring will be different, you should be able to splice it in. and same for the rectumfryer.
Starter relay, worst case place the starter somewhere where you can get at it and jump the 2 terminals with a screwdriver. Otherwise, any relay rated for the amperage will do, and others will work once or twice