Some old (but good) Tektronix scopes.
The Type 453/454 were the last Tektronix scopes to use vacuum tubes (a pair of Nuvistors on the input channel). Here is a website dedicated specifically to this type of scope. This one needs cleaning and alignment but does work. The manual is copyright 1967.
This 485 scope is a little newer (the manual is dated March 1976) and is a full 300MHz scope. Once it was cleaned up a little it has been working great.
From the era of tubes…
The old adage was to keep one hand behind your back when working with these high voltage supplies.