Questions have come up on the listserve lately about where to get
information about how to use a product and where to find the product -
about kaolin and gibberelic acid. Much of the research on this sort of
thing is done by Cooperative Extension and the land grant colleges ("Ag"
or "Tech" state colleges or universities). Both the researchers and the
Extension folks have, in my experience, been very happy to share their
knowledge with anyone who calls. For Extension staff, that's their job,
and for researchers, it's their vocation. They can tell you exactly
what research has been done, and what the results were. Occasionally,
you may contact an unhelpful bureaucrat, but if so, just try someone
else. Extension staff work with orchardists, among others, and would
also know where to purchase products in bulk.
For kaolin, and for gibberelic acid without any fungicide, it would
probably also be worth contacting the Rodale people in Emmaus, PA.