I know it wouldn't be made by you necessarily, but wood beads of all sorts are available online for a lot less money than that tool will cost ya!
This is a poke on our addiction Aaron, not your comment. "As are wood calls". Lol.
Along the lines of what Aaron is saying, I think you are better off with some calipers, AND I think you are better off on them not being perfectly round so they do look unique. Check out the jewelry making chuck by Ruth Niles for example, for another idea the girls may like.