Analog upgrade time

Alrighty Minions of stereo nirvana, here's one I am struggling with the most. I need to upgrade my analog equipment (you guessed it digital side is now creeping past analog side). I have a Rega P6 turntable and a basic Mofi phonostage going into Audio Research LS17SE preamp and to AudioResearch Ref 75 amp. Yes I like tubes. Sadly I do not know the name of the cartridge company.  I want to upgrade cartridge and phono linestage as a set that match well with each other and are well suited for a tube system. I prefer MC vs MM.  Thoughts please. This is the one area that is my blind side. Thanks in advance.