ah the bi-yearly inquiry into SanFu parts....
the closest I've ever heard from anyone is that "some guy" told "someone else" that some Subaru 360 parts "might" work.
Never heard back about it one way or another.
I'm sure these things have parts in common with a number of other vehicles from the same time period but there was apparently a reason their use was discontinued when they were used up. Lack of parts or incompatibility with other vehicles for parts could be one reason. Otherwise you would see more of them running around.
There appear to be a few of these (very few) floating about the USA, all looking for parts. Could be the same vehicle with different owners though, so the numbers might be inflated... So don't expect to find it listed in a parts catalog or any other web source. I can't recommend you to any other owners for help because I don't know of any.
I might get an email every other year from someone looking for parts, then I never hear from them again.
Part of the fun of these vehicles is the hunt for information (if you are up to it).
Many (well, one or two...) have tried in the past and failed. Perhaps you will be the one that cracks the code!