Looking to upgrade my old Conrad Johnson PV12

I'm in the process of downsizing speakers and replacing/upgrading my old cd player and pre-amp. I've just gotten the Avalon Ascendants and am using them with the Sonic Frontiers Power 3 monoblocks. I have an old Conrad Johnson PV12 and am looking to upgrade (as well as replace my old Meridian 508.24 but that's another thread). So, looking for a tube pre-amp replacement upgrade. Always liked the old Conrad Johnson sound but haven't heard their newer pieces. Looking for recommendations. Am fine with buying used and would like to keep it to $4,000 or under.

Thanks in advance for all recommendations.