Lol... Yes, he's not a spendthrift is our Alan
I've been using the best varieties of NOS valves for years, Telefunkens included, so am entirely familiar with their (undeniable) sonic superiority. Once you know the reasons why they're better than modern varieties [how they're constructed and the materials used], you simply wouldn't put anything else in your equipment.
The trick is getting hold of good ones, as even the NOS or NIB variety can fail, go noisy or just simply sound shit.
Therefore, to minimise the risk of that happening, I only buy valves from trusted sources, and from sellers who own valve testing equipment, thus can post pictures of the measurements shown, after key parameters have been tested. I also like to know a little about the history of where they've come from, such as when they've been part of old military stock, which invariably means they'll be good.
As for head amps, well I've been using them for years. My preferred way of amplifying the signal from a low-output MC cartridge has for some time been via a top-notch head amp, through a similarly top-notch valve MM stage, and for good reason. What I haven't tried yet, however, is a valve head amp. I suspect that if done well, it would have the potential to outperform an SS one.
I believe that Alan has made one such device, so it would be interesting to test it against, say the Denon HA-500 you're planning on getting, or some other quality SS head amp, and see what the outcome is
Marco.