Thanks, Dan, that´s life.
I´ve got three leads that I am trying to follow right now, perhaps someone can help:
1) there is this shot of Furutaka with Kinugasa in the background - there´s higher resolution available at
https://en.m.wikipedia.org/wiki/File:Furutaka_and_Kinugasa_1941.jpg but the scan is not good. There must be some better versions available like the second one on which Kinugasa is, unfortunately, cropped

(hi-res at
https://imgur.com/r/WarshipPorn/sIScl4D)
Attachment:
19411100 Furutaka with Kinugasa in the background_m.jpg [ 199.7 KiB | Viewed 1890 times ]
Attachment:
19411100 Furutaka stbd_m.jpg [ 269.61 KiB | Viewed 1890 times ]
2) there is another shot of Furutaka with Kinugasa in the background, perhaps taken few moments before the first one, that was published in Model Art Ship Special 50 but is far too small there to be able to see much:
Attachment:
19410000 Furutaka with Kinugasa in the background from Model Art Ship Special 50 p88_m.jpg [ 205.33 KiB | Viewed 1890 times ]
3) the same Model Art Ship Special 50 shows yet another photo on the same page, it´s Aoba according to the caption but this can´t be really told from the small picture and the sisters have been often mistaken, so perhaps there is a small hope, too:
Attachment:
19410000 Aoba or Kinugasa from Model Art Ship Special 50 p88_m.jpg [ 213.67 KiB | Viewed 1890 times ]
Any of these photos (or similar) in a better quality would be really helpful. The higher resolution the better of course (pls post a link or contact me via PM for larger images than this forum would take).
Thanks a lot!