Hi Jon,
at the first pictures i saw i thought also that this was the real U9.
But at this picture you can see the cut at the water line.
Look at the left hand from the Officer. You see the cut through the pressure hull.
Additional i never read something about a transport of U9 to Berlin 1936/37.
1942 U9 was transfered to Konstanza by a Culemeyer transport. I have a good Book of these Transport.
Regards,
Uboatfan