For those interested who stumble upon this thread in the future, "The varieties of persimmon containing great amounts of tannin are used, such as Ten'nou, Tsurunoko (Chocolate), Hourenbou, Saijou and Tamura."
Chocolate and Saijou or Saijo as you will find it, are found at nursery websites that deal in persimmon trees in the USA. I have both in my yard as small trees with first fruits this year, along with ten other varieties. I also admin the facebook group Persimmon World if anyone wants to join just send a request.
Doubtful anyone far north as Canada will get any D kaki variety to grow and survive, short of a controlled environment. Some group members grow them in large pots like figs and move them into the garage for winter.
I'm not a persimmon or kakishibu expert, just a guy with a few trees, but there are a few variety experts in the group.
Somebody wrote that our native persimmons would not or may not work. I have probably seven gallons going now, will let you know in a few years. As for the duration it takes to finish, I have an aeration theory that will be put to test some to see if it speeds things up a bit or halts or ruins it.
They "ferment" in open vessels. I'm not familiar with this and my experience says open top vessels turn fermenting things into vinegar. The nature of the persimmon being tannic is a very good preservative so not much should bother it by way of bad microbial things.
Edited to add: You who are searching for seed. I can help with that. D virginiana. I can send them anywhere, just pay shipping. They need a cold stratification period either outdoors in winter in pots that are kept moist or in moist media in the refrigerator for three months.