I would think any similar collet chuck would perform the same functions. Beall makes one that's well-regarded, and I know others have used collet chuck from littlemachineshop.com.
thanks guys! i've dropped him a line already. it seems that the only collet chucks that i can find are for small stuff, not quite like the one he uses. the search continues....
I don’t know if Raffan's a constricting or expanding one, here is a video by Bob Hamilton (bobham5) in which he makes an expanding one for a hollow project. http://www.youtube.com/watch?v=rfrldsntWbA
It may be a useful idea for other projects even if it doesn’t solve your current need.
i recieved 2 replies from him yesterday. it seems that style of collet chuck went out of production once the original nova chuck hit the market. still, i would have liked to get my hands on one of them....