A friend of mine says he might still have one of these in his mother's loft. Been there since the 60s.

He says it is in poor condition, and he thinks it dates from about 1935.

A 12-string, tuned to "C" (standard intervals) in stead of the modern "E".

I asume it is a flat-top because he did not say it was an archtop or F-hole. I assume also it is not a taipiece guitar because that's the sort of thing you mention too.

He says you can't get strings for it.

Any information? Ought he to be prepared to spend a fortune on it to get it restored? I am puzzled because I thought Gibson did not make flattops until later than 1935.