As a clue ..similar/sister with
SUN KUNG No 2 - IMO 7352438
http://www.shipspotting.com/gallery/photo.php?lid=2646333
built by Imabari Zosen in 1973.total lost in 1991
firstly need to check Imabari builts,
but of course it may have been built by other shipyards on the same design

Thanks for your input, Gerolf!
Brgds, Maksim

The vessel in the back could be Neringa or Kupiskis, both vessels passed often at the Boshphorus between 2005 and 2010, but there are many sisters of that type.
Gerolf