Isn't It Amazing....
....How the portable/convertible dishwashers in ads never made the kitchen look crowded or junky?
And how the ones in real life always did?
(Don't anyone hit me - I own a KitchenAid KDS-55 portable/convertible)
P.S.: "Conolite" is a laminate made by Panolam, formerly Pioneer Plastics. I would be willing to bet the Conolite itself is not actually rotted, that it's the substrate material it's glued to that's the problem. That laminate looks like it's dirty as Hell, probably with grease buildup or old Contact paper adhesive. I'd try some lighter fluid on it, and you might be amazed. If it comes clean, it can probably be carefully dislodged from the old substrate and a new substrate cut; you would then re-glue the Conolite to the new substrate and re-install the panel.