For $20, it is well worth it. There are numerous useful tubes, pots, etc, and of course, the power tranny is good for modest-powered tube amp projects, I wouldn't use it for much more than a mono PP or stereo EL84 or 6V6 SE amp. It definitely would not be even close to sufficient for PP 6L6GCs or EL84s...
It is very likely that you will find that most of the tubes inside are Mullard or Telefunken, as these were considered as being "cheap imports" back in the 1960s.
The power trannie is approx 350-0-350 @ 60-70 mA, 6.3VAC @ 3-4 A and a 600-1200 VAC @ a few mA for the CRT HV, this includes a series-connected HV filament winding for the 1V2 (typically) HV rectifier tube. Just cut those leads short, and cap them off with heat-shrink tubing to prevent any unwanted HV arcing, minor corona discharge, etc.
I gutted out one of these same scopes a few years ago, the CRT worked, but had a burned-in dark trace across the face, and a couple of the PSU electrolytics were leaking out their contents
I'd have to dig deep through the boxes in the cellar to find it, but I think I still have a manual for these scopes.
/ed B