Not seen these recently, but I know they exist and I havent dreamt it up as ive seen them with my own eyes in the past, lol
Basically, a replacement boot, but mega stretchy rubber than you can manage to get over the CV without taking it off the shaft, you have a kind of cone thing that you slide the boot over to open it up enough to get the small end wide enough to go over the whole CV then it shrinks back down to fit the shaft.
Anyone got any links to where to get them from, or specific makes to ask for etc, im assuming most motoring stores could get them with a decent enough description?
cheeRS