I take it Primrose aren't selling their supply. Would it be worth joining and buying as a member? If not you might like to join Papermakers of Victoria. We still have a reasonable supply but only sell to members. I bought it from I think a company called Quick which I found on the Internet many years ago and of course I can't find it now. Anyway I had to order a full crate which was about the size of a small car so WAY too much for one person.
Another option might be ordering from Carriage House or Twinrocker in the States. Also there is an American guy who goes to the Philippines and takes back gampi which behaves in a similar way to kozo. Last time we spoke he thought he might be able to precook some slabs of gampi that would satisfy our strict quarantine.
Not much help is it but a few ideas, also Peter Stamford brings fibres in from Thailand and he has some kozo that looks like it might have been cooked and washed and then just spread out. I think he sells it for decoration. Primrose will probably have contact details for him.
Your best bet is to contact Primrose Paperworks, they have a website and should have kozo for sale. About 5 years ago I organised a large shipment from Thailand which was shared between Primrose and Papermakers of Victoria.
Where did you do the papermaking course? I am going to Japan next month and am always interested in paper, won't have time for a course and need to spare hubby from too much paper but I'd still be interested.
PS love your books.