"Glenn Croft (RIP) told me he used buy Telefunken ECC803S for £5.95 a pop. Now they sell for $1500+"
You can spend a lot less than $1500 each for a pair of Telefunken long/smooth plate 12AX7s tested and strong. In fact, you can even get a pair for $125 right here on Audiogon if you look for them.