I'll confess I'm glad the machine has gone to a good home, irrespective of how it found its way there...
I'm not so sure about any intervention by the military to keep it from the domestic market. In the metal-cased form the machine would have had little appeal to private buyers, but it does appear to have much in common with my 1948 Model D ( see "History" or "Model D" sections at
http://www.ferrograph.info/ ).
A few weeks ago I found a website offering (though currently out of stock) a CD-ROM containing "all" Ferrograph service manuals, certainly including the Model D, but I can't seem to find it now. I wonder whether a can really has gone missing, or whether a place was provided and never filled - the two that remain somehow seem likely to provide smoothing enough for most requirements! The amplifier does look very similar to that of the Model D from what I remember of it, so I'll take a look in there when I can and report on findings, if full information hasn't come your way before then. I'm fairly sure the domestic version has a bigger, probably 8", loudspeaker, and doubtless input/output arrangements differ, but maybe not much else will.
Paul