80's custom shop yes not sure about after. "Mr 500" JB will probably know.
I have a memory of one with Damascus bolsters.
In one of my early trips to the Blade show (2009?) I spent several hours looking at his display of 500's since they were right next door to my 112's. What really impressed me was how compleat it was, including all the rare stone inlayed LE's . So if there was a brass framed 500 he would have it. .
Not sure on the 501 in brass, but how about the 55 which would be less bulky than a 112?
Photo borrowed from the internet.