Jeremy,
My suggestion would be to call Beaver Coach Sales in Bend Oregon. They will most probably have one in stock or be able to tell you where you can locate one. I think that your control was made by SCS instead of being from an automobile manufacturer because it (2000 Marquis) is designed to run two different blower motors. A/C controls for a car are never designed to run two blower motors with the exception of large SUVs or vans with rear air and they usually have rear controls for the rear blower.
Even though SCS is out of business now, most of their dash air business was bought by Victory Climate Systems (VCS) in Fort Forth Texas. So they may be able to help you also, however since they are a manufacturer, their parts department will not know which control panel fits your coach.
Gerald
