How can we of assistance? Looks like you've identified the problem to be a band switch wafer. What's wrong with it? Something lose? Something missing? Something broke?
Is local xtal oscillator oscillating to spec for 40 meters band? It is quite possible, if you bought it used, someone tried to mess with it and it could be just out of alignment. Fortunately, user's manual has full circuit diagram and alignment procedures.
Have you tried Deoxit? Just a little bit of it does wonders if it is otherwise physically intact.