Some of their older preamp models provided optional built-in phono stages, but I am not aware of any separate phono stages they have produced. And I believe that those built-in phono stages provided somewhat lowish gains, that were only suitable for use with LOMC cartridges by virtue of the relatively high gain provided by the line stage in those preamps.
Just guessing, but perhaps one reason they apparently have not produced a separate phono stage might be that application of their ultra-wide bandwidth philosophy and circuit expertise to a phono stage might result in significant design challenges related to avoiding RFI (radio frequency interference) issues, given the very low signal levels that are involved. And also given that the frequency response of LOMC cartridges typically has a resonant peak somewhere in the RF part of the spectrum, resulting from the interaction of cartridge inductance with phono cable and load capacitance.
I don't doubt that they could have overcome those challenges if they chose to, but perhaps they felt that it wasn't worth the effort given the competitive landscape.
Regards,
-- Al