There is some information on 860 Sq NAS on Wikipedia: https://en.wikipedia.org/wiki/860_Naval_Air_Squadron   The article gives 2 locations till December 1943; RNAS Donibristle in Scotland and Maydown in Northern-Ireland so that might give some direction in your search. I would try to find out if there are Historical associations in those areas/counties, and contact those with the information you have along with the photo. Those buildings might very well still exist.   Also, maybe consider asking on the Historic Military Vehicle Forum. While mostly vehicle-related, most members are from Great Britain and you never know if they might have any information for you. See the 'Reseach Centre'-section of https://hmvf.co.uk/    

Here's the Pre War Blue Uniform one, a White Strap,  White being the Corps Color the regiment was in, the XVIII Corps. We see on the Field Grey one and this White one the Roman Number II, this being for Kaiser Wilhelm II, so the regiment no doubt gets its royal title sometime after 1888, the year he began his reign.  

Sir William Jock Whitworth

His name is Johan George Hoffman born in 1922. He went to military school in Soerabaja Indonesia. When the war broke out in Indonesia in marz 1942 he went from Australia  to the Uk. In may 1942 he was in Falmouth UK. January 1943 he went to Eastleigh. September 1943 he became part of the squadron 860. He died december 1943 by a plane crash with the swordfish in Kilsyth. He departed that day from Londonderry. 

here are more pictures of my HJ knife. weather is bad here so couldn't take pictures outside. hope these will do.

had this on for a good time. maker and district P hallmarked plus vet etched his social security number on the scabbard throat - i guess so it wouldn't be stolen by another vet.

nice little knife with a 6 waffen

here are better pictures of my DLV dagger as ask for. did not know it was ok to show the swaz here so it is now.

No need to cover up the swastika here.. Would like to see the whole dagger and markings   Leigh 

Post images of the HJ insignia as well...   Leigh 

Do you have any more information about your grand-uncle? Name, unit, date/location of death, that kind of thing?

A couple more shots from that 1947 Trip.   First in Northern Waters still, then later into Sunny Climes. In the warm weather one, note the two Royal Marines off in the background at attention, I wonder why they're like that, their escort around the ship???