I make my own as I bought full red squirrel pelt a few years ago and it was a good buy. Also shot a grey that has supplied great dubbing. A coffee grinder is you friend for mixing as Brian said. I often just clip from the pelt. How much do you need?
It makes excellent Dry Fly Dubbing. Floats well and easy to dubb for flies like the Adams. I like the course longer fibers for Wings on dry flies, float like a cork.