Just aquired a trk-12

[dtvmcdonald]

Its not a matter of "ease".

Its a matter of "very custom" and "big bucks".

With big bucks one could even dispense with a graded seal
by attaching the gun to a Pyrex based pin base or use a custom
array of pyrex to metal seals. That last method is absolutely guaranteed
to work and is easy for a good glassblower, but not cheap. You would
of course need to use loose socket pins on a custom PC board.
I have actually used such devices. Its common in the scientific field.
You just have to think outside the box, and damn the inauthenticity.
You'd end up with an all-Pyrex tube, a good thing.