GAS I suspect is the case maker, as the hallmarks are standard and not import hallmarks.
Yes, the dents I hope/imagine are from skiing falls etc. he was the top skier in the British Army back then, rather than the more realistic reality of staggering home up the road from The Rozel to home 1/2 mile after rather too many Scotch whiskies! Retiring at 40 from the army, made for a lot of spare time...too much in my book! Jersey is a small place as you well know ;-)
Still, it is special to have.
Cheers,
Tim