But they're fairly easy to make. All you need is a wood rasp (although a lathe would be cool too ). I originally got mine at Shaolin. The shaft was made of white wax wood, and you know that's just about the tastiest wood if you're a termite, so it got exposed and eaten in a matter of days. I salvaged the head and put in on another shaft. I've also made my own.

BTW, I'm assuming you're talking about the unique hammer-like head Bodhidharma cane, akin to a buffalo horn stick. Some use regular umbrella-handle headed canes.

For reference, see my article The Crutches of War: Bodhidharma's Legendary Fighting Cane in our 2002 Shaolin Special (January/February).