American Woodcrafters has birch for around $25.00/100. They make great arrows, but you have to watch out for grain runout and knots. Just be sure to visually inspect them and flex each one, and you should be good to go. Most of the 5/16" I have played with run in the mid - 40's, to a max of about 55# (only one or two) and a low of less than thirty pounds, again only one or two. There are a couple of threads on this subject, too. Good luck!