I be-leave this to be the OTTAWA (date of photo.26.6.64.)put on e-bay as View from bridge of 260,000 tn.tanker ?

dates seem right but I don't think Ottawa was so big maybe around 100,000 ton could be Narica or Nacella

Yes, OTTAWA was 93,000dwt and if it is her the photo was taken a few days after launch.

http://www.tynebuiltships.co.uk/O-Ships/ottawa1964.html

Can't see anything else about this time that would fit.

Here is another picture from a different angle which may help.