Do any still use an older high end tuner from the past?....

Richard M did his RIMO filter Mod to my MX-110 Z
his work thru Audio Classics very highly recommendable for those w Tube Mac tuners to keep running top notch 

And of course, Rich's work on MR78'a is also highly recommendable which of course is a solid state tuner. Except if you count a one off version of the MR78 which in fact is tubed. But that one is safely with Rich, and I don't think he's interested in making other one. 

One correction and one addition.....
Over the years......

Lux T110, Tandberg 3001a, McIntosh MR78, Scott 4310 (Foster Blair fixed it up for me), Three different Scott 310-B w 335mpx (all fixed up by Foster), Yamaha CT-7000, Sansui TU-X1 (aligned, upgraded, recapped), Magnum Dynalab MD108.

By far the best is the only one I still have.  The Sansui.  One good classical station in the area still makes it worthwhile.  Channel Master TV-7? Antennae mounted in attic.  Incredible sound quality.

One of the Three Scott 310-b I had was my prior vintage favorite, simply terrific.  The 4310 was probably the most exotic but a little scary with all the controls and so many tubes.

My MR80 (McIntosh) is (i think) over 25 years old and still pulls in the stations

I have one of the very first Sequerra Tuners ( S/N 1006 ) . Still sounds great and in perfect condition about 40 years after I bought it  . It is a strange fit for the rest of my system which is at the tippy-top of the cutting ( bleeding ? ) edge .