A manual bilge pump of the diaphragm type that can be stroked/pumped from the cockpit is standard (basic) equipment on sailboats. These are rated at
ca. 16-18 gal/min. I suppose that means the person pumping must complete a cycle (i.e., draw/discharge) every second or two, which might get you near 1000 GPH if you could keep it up for an hour.
Nevertheless, it would be unwise to disassemble the manual pump’s pathway and to install an electric (impeller type) one in its place. The electrics are installed to drain the bilge of incidental water, sometimes wired to a float switch that turns them on at a certain water level. Some pumps activate on a preset cycle—no float switch. An impeller pump rated at 2200 GPH will likely deliver only half, if not less, of that discharge rate after installation, even assuming nothing gets sucked into, thus fouling, the impeller.
Manual diaphragm pumps do not foul b/c there is no impeller. They can pass solid debris (bits and pieces of little s**t) through the hose. And as they also do not require power, they are in those ways more reliable—but you (crew) have to pump ‘em. Here’s to good CV stamina.
Neither of those pumps could likely keep up with “serious” flooding. You’d need an
actual, realized rate of near 3000 GPH to keep up with a modest hole/crack that cannot be quickly plugged. So, unless you wish to get real serious about emergency dewatering capacity just leave the manual (i.e., standard equipment) as it is. Install a 1600-2200 GPH impeller pump with its own discharge hose and port. Build on that later. The pump and accessories cost maybe $250. Having a professional installation at around $100/hr labor (if you are lucky) x 2 hr, etc., estimates out at about $500.