Try to find a type of wood called Purple Heart. My sensei, who is a wood worker by trade, makes all our weapons, bokken, jo, tanto, and he uses a wood called purple heart. It is extreamly hard and tough, but light as well. I'm not sure where he gets it from. It is easy to maintain as well, just polish with mineral oil about once a month. Hope you can get your hands on some. Good luck!
All the best.