The pricing I've seen ranged from about $7.00 to
$44.00 each
used and tested but so far, I haven't seen any prices for NOS
parts. I do like the $100.00 per digit though :).
Let it be known that I have some NOS minitrons*,
for the truly desperate.
I used some back in ~1970 and was able to find a bunch
more just a few years ago, that are still unused.
Archer catalog #276-051, for reference, 100,000 hours
stated lifespan.
John A.
*I was going to say 'evacuated DIP's but that has a wrong sound to it <g>.