Can't really comment a great deal, I've used the moutpiece from one, and it works. If you don't want it, let me know. I'm always hunting for new bits.
Try
www.therebreathersite.nl and similar places and you'll find a stripdown somewhere of the unit.
If you've got a functioning unit of almost any type commercially available, you can convert it to a useful CCR, just depends on how much the donor unit costs and whether it's worth it. Right now, I'm kind of wishing I'd have just spent the money on a new KISS...
Digs.