I replaced mine with this one from FCP Euro which also has a metal impeller:
https://www.fcpeuro.com/products/bmw...in-crp-wpr0047
Cheap price and lifetime warranty, can't beat that!
Changing the water pump is not that hard, just takes a little time and patience. The hardest part for me was getting the belt back on the pulley.
I'd also recommend changing your thermostat and temp sensor while you do this job as preventative maintenance since you're already working in that area.
