If you are referring to the smoked plexiglas
sliding doors above the ice box/stove (on my 1986 boat), I think you have a number of pretty easy choices. I would bet just about any hardware store that sells cabinet door handles would have something that would fit. If I were replacing mine, however, I'd simply remove the doors, take off the old handles and replace them with a piece of teak, mahogany or any hardwood you have by cutting a few pieces about 3/4" high and 3 inches long. Screw them in from the back side.