There are multiple pump manufacturers out there and there are all pretty much plug and play with some minor modifications. Just Google RV water pumps and you will find an assortment. Of course a fast fix is to leave the pump alone and add a back-check valve in the water line, if you have room for one.
However, is there no way to extend the overflow line on the tank so if it does fill, the water does not flood your camper?
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SC