There is no need to worry about spare parts. It is Shindo's policy to have parts on hand for repairs. I believe the number quoted in Art Dudley's article in Stereophile was that if Ken has 100 of a given part, 40 will be used for the production run of that particular unit and 60 used for spares. When Shindo reaches that quota, the unit is retired from manufacture.
What's cool is looking at the Japanese used equipmensites to see the various models that have been retired. A lot of people are only discovering Shindo now in this country. But Shindo has been around for over 30 years (older than all but a handful of high-end companies). There are so many different Shindo models using stuff that only hardocre DIY guys have ever heard of.
Kudos to Jonathan for making this happen. I've been trying to get Matt Rotunda to get Jonathan to put together a Shindo history website with cool pics of the older Shindo gear.