I don't remember when you said he retired, but having films(pre-video days remember) with sound would be a tough ask! Few sound films exist from the 50's and 60's. Heck my first SOUND super 8 camera was 1978! I only wish we had better stuff in the old days, but thats the way it goes!!! Amazingly today I have footage I shot in the sound film era, that transferred and is better looking than early video! We probably have some films with him in there, but mostly we don't know dates or if we do, don't know the crews. Was he on any of the series of June 3-5, 1968 runs? We have some of that stuff.
Greg