Where I work we use Electro Harmonics preamp tubes in 4 items of gear that we make, that is until this last production run that we will start where we had to get them from Fender / groovetubes at a cost of 2 bucks more per tube!
If you do find what your looking for then for the end user it will be a good bunch more costly!
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
I bought most of my tubes like that through ebay sellers. I realize a full time shop can't do that, but it works for me. I don't know how any of those sellers are impacted by the current events.