Sven,
There is a good account of the brief career of U-247 in "Lost patrols, Submarine wrecks of the English Channe" by Innes Mc Cartney a well known diver of Cornwall. So far, the wreck was first observed in the 1960s but does not seem to have been dived since. Approximate location is 49.53.9N 05.49.7W. There is also a photo probably taken on commissioning day reproduced from an U-Boot Archiv original.
[www.periscopepublishing.com]
is the link where you can find that book or even contact Innes Mc Cartney.
Have you also tried
[uboat.net]
Provided you become member you will have access to the "conning tower" section where you can find more details as for example a crew list.
Hope this helps.
Rgds
Yves