I can't be of any help with the civvy cross over part numbers, but I can tell you that if your original water pump housing and impeller is still in good shape, you can rebuild it yourself with a kit from Saturn Surplus. It comes with a new shaft and bearing, and seal.http://saturnsurplus.com/m151/images/wpumpkit.jpg
Best of all it will only run you about $23 for the kit. If you have a press or have access to one, it's really easy to do.
Hope that helps.