In 1968 you could be a nice Cadillac for about $5000. Nobody bats an eye at $50,000 for a nice Cadillac now.
A Marantz, 7C, 9 and 10 cost you a cool $1600, another $700 for the Dayton-Wright ESLs, $200 for a turntable with arm and cartridge and $200 for a decent tape machine (unless you got a pro model in which case it was $1500!). Total with cheap tape deck: $2700.00
Inflation has devalued the American dollar well over 10-1 in the last 40 years. If you had to buy the same stereo today: $27,000. That's with no performance increase over 1968! $200 30 watt/channel recievers were available in the US in 1968 and were that way until 1988- we grew up thinking audio is the one thing that is cheap. Good audio is not and never was.
In 1970 a 6550 retailed for $15.00! Enjoy the cheap prices we have on tubes today- it will not last forever. It should be no surprise that an NOS tube could cost $100 or $150. Think of the American labor that goes into making an American-made output transformer and see if you can even build one for less than $100 (not sell- build!) that has any performance or power handling ability.
The 'audio costs too much!' mentality is entirely unrealistic. It ignores the real world we live in- unless you want to complain that *everything* costs too much and then I'm with you :)