Phono Stage for Conrad-Johnson CAV50

I am looking for a phono stage for CAV50. My system:
Spendor sp2/2
Rega Plannar3 turntable

Any idea? Phonoe stage or a pre-amplifier with phono stage
(saved for future upgrade?)

Consider a used Conrad-Johnson PV-9A (preferred) or a PV-10 full function preamp. Both would be a good match for the rest of your system and give you very good phono stage. For either, you'd need to best off using a cartridge with an output of 1.0mv or greater.
I am using a old Linn K9 MM cart.. Not sure what's best fit...
I don't know the specifics of the K9 cartridge, but the current Linn Adikt moving magnet cartridge (which replaces the K9 in the Linn lineup) has an output of 6.5mv which is a very high output cartridge. I suspect the older K9 has similar high output. This output will present no problem for the preamps I've suggested.
I got a Black Cube SE Finally, which received lots of good reviews. I am curious how it compare with these phono stage coming with full function pre-ampl.....
Congratulations, Smileshopper. The important thing is always: how does the equipment sound to you? Is it meeting your sonic priorities in what it does? All of this gear is different, each piece has its own strengths and weaknesses, and all of it interacts and balances differently in a system to create a synergy (or fail to create synergy) that ultimately creates the musical experience for us. The important thing is that you are now set to play your vinyl. Enjoy!