Though I really doubt anyone will read this, much less the owner of the crafton guitar (nice one, by the way!), I’m gonna post this anyway.
That guitar you’ve got there, is most likely named “13a”.
I happend to have bought myself a crafton about six month ago, and managed to get in contact with the guy from Gothenburg(well, at least that’s what his accent told me) who seemed to know just about everything about this company. Great guy.
T’was finished on october 13th, 1947. number…11 of 27 that day? something like that. Perhaps 23 of 27.

The difference between mine and yours, is mine’s got a mahogany brown finish on the spruce top, to match the mahogany neck, sides & back, as well as one “missing” inlay on the 3rd and 9th fret.
Sold for about 85kr. I’m afraid I don’t know how much that would translate to in these days. 🙂
From that I gather yours is a 13a.
Although, I might accidentally be switching the design of a & b in my mind – it might as well be 13b.
And do take care of that guitar of yours!