Vintage Fisher M-Scope

I am trying to find info on or from collectors of old detectors. I have a M-Scope from the 50's and would like to know more about it than I got from Fisher's website. Anybody got a 'History of Metal Detectors' type book? This model has a blue case made of wood by Fisher himself and the headset is bakelite and I think with new batteries it may still work. I was told that the year of manufacture is in the serial number but of that I am not sure. It takes some C cells and a 67&1/2 volt battery.
To Hakzaw:

There is another forum that specializes in old, vintage collector Detectors. Not sure if I can mention their name on this forum so email me... and I will tell you the name of the forum. Is this a 2-box detector? The 67.5 volt battery has been discontinued since the late 1960's or so. Also does it have vaccuum tubes ? These will all help determine the age? JOE
vintage M Scope

I too have a vintage fisher two box detector Model ME Z. Called the Fisher company in California and the guy said it took nine volt batteries. Yet it's not set up fo that type of battery. It has those horse shape connectors for battery conections. Hope you do better then I am in getting this thing running.
update on my M-Scope oldie

Seeking info and/or offers on a Fisher M-Scope circa 1955 model ME-Y with serial #L 55125(possibly the '55' is year made:1955). It's a two-part detector with original bakelite headphones. The cases are made of wood and the side I looked into had one vacuum tube and I suspect more inside the other half. Uses two 'D' cells and a 67.5 volt battery(obs.)Only thing I know of missing is some sort of threaded handle that attached to the unit with the meter, headphone jack and sensitivity dial. It shows some signs of use but no damage. Great decals in fine condition. A little rust on the hinges. Missing instruction book. Hand made by its inventor(many believe) in his garage behind his Calf. home. This is the great-grandaddy of your modern day models. My first and only detector, I know very little about detecting and have not tried to put power to this unit. HELP(also need help on how-to post pics if you would lioke to see them)Thanks!! Hack