Maybe not the ultimate, but the phono section of the Audio Research SP-6B is really good. It is very alive (compared to the ML #38s I had for many years). Great dynamic range.
It is known for its "warm", but not syrupy sound.
(Gee, did I just write that? Totally deranged mixed metaphor.)
These old AR preamps can be had for $1000 to $3000. Factor in about $1000 for new tubes and electrolytic capacitor replacement and you have a killer phono pre.
Use the tape outputs. This way, you are using only three of the six tubes so you can invest in some great NOS for the phono section. You can populate the other three tube sockets with lesser quality tubes as they aren't used (but please put a tube in each socket. You risk damage if you don't).
The AR SP-8 and SP-10 are also great candidates.

