I have no experience with using the cytokinens for rooting. I am more familiar with their inhibition of the abscission process and their ability to increase the longevity of plant cells. There are two "raw" sources of kinetin.....human urine, oddly enough, but let's not go there.......and yeast. I had some success in extracting kinetin from yeast by allowing common baking yeast to grow for a few days on a gelatin medium with a small amount of sugar in it, in a warm environment. I then skimmed off the yeast and put it in a deepfreeze for a couple of days to disrupt the cell membranes, allowing their internal fluids to drain out. After thawing and letting the mixture settle, I skimmed off the cloudy liquid part to use as my source of kinetin. Of course, if you had access to a centrifuge, you would have a quicker and more efficient separation of fluids from solids, but, you can manage without it. It's cheap and not all that difficult .

Very limited experience with using kinetins for orchid seed germination - nothing of significance to pass along.

The link below is one source for kinetins, auxins, etc. I don't know if I would call them inexpensive, but they are comparable with most other sources I have found. Their service is very good, and they are small enough to take the time to talk to a customer. The technical notes in their catalog contain a lot of info.

Here is a link that might be useful: Phytotechnology Laboratories