Dropping from the higher gain 12ax7/100 down to a 5751/70 or a 12aT7/60, just having the lower gain should make a difference to help calm things down some.
While I currently use mid 1960s Mullard Blackburn 12Au7 and 12At7s myself in my amps, the most important thing discovered is sourcing tubes from a great tube reseller with the best testing and validation equipment. Truly matters.
For re-issue tubes, I’ve tried and still own many [if not all] of the new production tubes mentioned here above, they are nice backup test tubes for reference checks once in a while. While not as musical, some of the new PSVane small tubes and Genelex Gold Lyons have worked okay for me in multiple amplifiers. Try that 5751 for a while and maybe a good 12aT7 next in those spots, and you might be good enough, and just listen to the music.