If you want to see a Grumman J2F Duck watch Murphy's War on YT.
I don't know where they got the submarine but it wasn't WW2 vintage either. Probably because most of them couldn't be recovered (sank).The type of aircraft used, a Grumman J2F Duck amphibian, never served with any British or Commonwealth navies. Equally, the camouflage does not match the markings used: it carries early war British roundels on a (very) late war colour scheme. Understandably, however, there were quite a few surplus J2Fs around in the late 60s, as it had been used by quite a few South American navies for several years after WW2. It would have been impossible to have a more authentic aircraft, such as the Fairey Seafox, which was probably the most common shipboard naval reconnaissance floatplane in the early years of WW2.