I've been looking and I can't find something close to what I need. I would like a thing that slides into the camera's existng cold shoe and that has its own cold shoe that would be placed a little behind the existing shoe. The closest I could find is this thing:
View attachment 410154
Universal 1/4" Screw Interface:Central 1/4"-20 threaded hole for securing to mini tripods, pan-tilt mounts, or cold shoe systems. Red anodized aluminum construction ensures stability and durability. Compact Aluminum Alloy Design:Lightweight yet robust aluminum alloy body (13g/0.46oz) with...
I'm sure that this will not do what I want, but it does give a good idea what I'm looking for. in this instance the side with the screw would slide into the shoe (this device is probably too wide, and too thick.) The existance of the screw would actually be good as it would be used to lock the extension in place. I also saw something that exactly what I'm asking but it was too long (maybe a 2-3 inch extension) and no longer made. The side of the item above is more or less the scale I'm looking for, i.e. it extends the shoe backwards about the lenght of a shoe.
I may just end up buying one of these, then going at it with an angle grinder to make it fit, but I'd really like to find something purpose made. Has anyone seen something like what I'm looking for?