Beer cooler commission

My skull chalice is a big hit at parties, and as a result I now have a commission to make a beer cooler in the shape of a decaying hand.  Making a beer cooler will neatly sidestep a problem I have with the original chalice, which is that it isn't large enough to accommodate a whole bottle of beer.

The beer cooler commission will be based around a ready-made beer cooler.  I could get some neoprene and make one up, but why bother when I can get a pre-made one more easily than I can source neoprene sheeting?  The whole purpose of a beer cooler is to, well, keep beer cool, so I think an insulating lining is quite important here.

The commissioner specifically states he doesn’t want any bones sticking out of the wrist, as he feels that is a bit passé (which it is).  He also wants a grey-blue tinge to the skin, so we're shooting for something that's been dead quite some time here.
I think I've mentioned before that I tend not to do a whole lot in the way of preliminary sketches.  That's mainly because I like surprises.  I did, however, do a quick (and very crappy) sketch of how the hand will wrap round the cooler.  I can neither confirm nor deny that I may have done this during a business unit meeting at work.