http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7574691095&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1

I don't think it's a prototype. Obviously home made. Whoever did it went to an incredible amount of work. It is definitely unique. If I had the money, I would be bidding on this one.

NOpe not a prototype, the table reminds me of German cameras. remember the Speed was an amalgamation of several other "graphic" cameras...

The front standard and lock came from either the Auto Graflex or the 1A Graflex.
The viewfinder came from the O Graflex or the Kodak Speed 1A
The focal plane shutter with it's hardware came from the focal plane attachment to both Century and RB Cycle Graphic cameras.

So except for size and possibly back configurations, a prototype Speed will look very much like a production Speed.

Now when they were working on a model change for the Speed, the prototypes were left without leather except when it's thickness was needed, so most of the body was naked but you'd find leather under the hardware and a dot of leather over the bed release button.