How do I buy one? and how much?
First, you have to get on the wait list next time it opens up in a few months.
The cost of the brush will depend on the handle and the knot you choose. The last one I did ran about $55 for the handle and I bought my own knot for it and sent it in (the knot was another $50). This one I'm using a higher end knot. If you use an inexpensive synthetic knot you might get away with around $75 or so. A really high end badger knot might put you at the $200 mark. So the price varies quite a bit depending on the knot you choose.