Pumps are a pretty generic thing and not really specific to a boat. All they do is pump water through a tube - from under the boat to the side of the boat where it exits. March is a good/common manufacturer.
I'm sure you know where the seacock is to close off the supply (and, if needed, to prevent sinking your boat). From the seacock, follow the hose and you'll quickly find the pump.
It wouldn't make sense to have two pumps for such a simple thing with relatively short run.
There's usually good info in the owner's manual, as well.
