It seems like you could start with the CT foot ascender (right foot for the right hand so you could disengage it with you thumb). The gauntlet would be nylon webbing or elastic and 4" wide with a thumb loop ( imagine the Gecko leg strap and a roller blading wrist guard combined without the plastic support). The cam would be a reached via a loop that would sit at the base of you hand where it joins to the wrist. The back of the cam body would have velcro on it and would adhere to the palm and velcro on the front of the cam body so it could fold down and stick to you wrist when you don't need it. Maybe I'll draw a picture later.
While we're at it, how about a tsurugi scabbard for you for arm that with the push of a button the blade deploys out of it like a switchblade (straight out)... X men meet Arbos