Shurflo 4008 repair kit

Due to a subpar job of winterizing (my fault), I had to replace the water pump on my brand new Jayco Jayflight. After I replaced the pump, I examined the old one and found that the upper housing was cracked. So I'm thinking that if I can find a new upper housing, I can repair the punmp and keep it on hand as a spare.

Problem is that I can't find any source of repair parts for Shurflo pumps. Anyone have a line on a reliable parts provider?