you`ll probably find Skat and Solas impellers. You`ll need to get the correct pitch.
The previous owner reported a gain in top end with skat`s, while I have slightly less top end but better bottom end with the Solas impellers.
Not any one`s brands have the same pitch, even tho the pitch numbers would be the same. The root angles and overall design, swirl, over lapped blades separate the brands... you`ll need to read up on what you would like and go from there.
The OEM impellers are a very good compromise of both bottom end and top end.
BUT, the aftermarket impellers are far more efficient...
Since you are in AZ, try giving IMPRO`s a call, they are in CA, and see what Dave has to say... good luck...