I think what you have here is CRT's for super high end military use.
IIRC F-15's & some other aircraft used Zenith EFL or FTM CRT's. Zenith
is all but gone including CRT mfg & rebuilding. So if you need a new CRT
in a half million dollar system they can rebuild it but the cost would probably
in the tens of thousands. You get what the market bears.
Zenith also built the monitors used back in the 80's on GM personal
luxury cars ( Toronado, Riviera ). They were monochrome & a rebuilt
was abt $800. Never worked on one but I think most had bad CRT's
after many years on the road.
Interesting stuff but them doing consumer CRT's is like us spending 2 hrs on a ten dollar radio & charging $5. In that time you could do $200 + on
other repairs.
73 Zeno
LFOD !