Look at the pump
The manufacturers name or the model should be evident somewhere on the pump. Also check the sizes of the hoses in & out and the size of the pump itself ( probably the diameter) and with this info, any marine supply should be able to help you, as Mike suggested. Most production boats like O'Day's uses proprietary, off the shelf, parts from a variety of suppliers for nearly everything except the actual fiberglass mouldings and perhaps a few castings, so unlike a car where you're dependant on the dealer for nearly everything, the equipment on your boat should be available from a variety of sources, including the OEM supply if still in business. Rudy at D & R is an invaluable source for stuff that is uniquely O'Day, but I hate to think that his valuable time is taken up by questions about parts that are common to many boats and readily available from most places like West, Defender etc etc
