CRT's yes. remember how they told us not to sit right in front the (old CRT) TV when we were kids? They were right...thoise things leak low-level x-rays. The older the design, the more likely it is to be a hazard. If you gotta fly an old plane, pick one with steam gauges

Antennas should be sufficiently attenuated by the hull. The radar is the freq you need to worry about, hopefully there's not much of a back lobe getting through.

TRU's (and all the onboard electrical powers systems) are far too low frequency and voltage to be a hazard in the known dielectrical-thermal realm. If you want to be concerned with non-thermal health risks...well that borders on tin-foil hat paranoia (in which case the tin-foil hat might help).

Buzzing around in the flight levels for decades will give you a small, barely measurable but nonetheless real increase in cancer risk. If you can avoid big solar flare days, do so.