Dr. Eagle:
The housing issue is fixed by buying the whole pump kit. I never go to the energy of trying to find one of the blue impellars, I change it every year without fail and always carry a spare. My comment to LavyMan was because after doing a ton of work to fix all my water leaks we went out on a one day trip in my boat and the impellar housing was cracked and leaking like a seive! I replace the impellar 1-2 times a season but only replace the housing if it shows signs of wear.
Chuck wink