1982 3607 9 liter International raw water pump

I recently purchased a 1982 3607 Carver with twin 9 liter 551 International V-8 diesels. Crusader marinized these motors for Carver. The issue I have now is locating parts for the raw water pumps. Sherwood manufactured the pumps, but have discontinued the particular model. The model number is F75 and some parts are still available thru dealers with old stock. I'm looking for a new or used pump and a parts supplier if possible, also if anyone knows of a replacement pump for this application. Any help in this matter would be very much appreciated. Thank You, Duncan