There used to be an outfit in Florida called Reference Line. He made an exquisite passive preamp with numerous inputs. I have his model 3000 which I will probably never sell. Mine is copper wired but he was more famous for his silver wired version called The Pre-Eminence, as I recall. There were dual mono units, balanced units, and even one with a motorized remote volume later on. These are rare today though he sold a lot of them back in the 1990s.
If you can find one the price will be under $500 and the sound will rival anything out there. I compared a PreEminence to a CAT preamp had I had back then and actually preferred the Reference Line. Keep in mind you'll need outboard phono with this choice.
Barring this suggestion, I doubt you can beat that Superphon.
