Swamper,
It is clear that you want to drop in some other type of motor, but in reality you won't be set-up to do it next week. So how long is your current motor going to run with a broken water pump? If it were me, I would get it fixed immediately before the whole motor is junked and you find yourself with no ride to work, and trying to figure out the cheapest way out of the mess you're in. Inevitably, the cheapest solution will not be the best.
Poll