I'm going to go out on a limb and disagree with much of what has already been advised to you. I get your desire to concentrate on hollow state gear, and stick with the older stuff that interests you. What you need is a simple scope that will let you troubleshoot the older gear while not being a headache in its own right. For this, all you need is something that has more bandwidth than what you're working on and doesn't come with constraints that limit its utility. Small size would be an advantage, because you don't need another large item in your collection.
Tek's 7000 series are beautiful scopes, but they are WAY more than you need, and they are just as big as the parts you're working on. I strongly recommend that you stay away from analog sampling devices, other than the ones you're trying to repair. 50 Ohm inputs and sampling diodes that are expensive, and likely unobtainable, and die if you give them more than 2 V are not what you want in your troubleshooting toolkit. You want something that's cheap, straightforward, and not likely to turn into something else that needs repair.
I'm in something of the same boat as you. I work on older gear that has tubes and is mostly fairly low frequency. I have a 564B and a 465B, and I love them both. Then, a few years back, someone gave me a TDS220. I thought it was a stupid little 'scope, but I accepted the gift. Sure, it's 100 MHz, but it's tiny, a small boombox, and it's digital, but it's become my troubleshooting tool of choice, largely due to its small size and weight. Nothing fancy here, nothing to write home about. It just does everything I need it to and is easily portable.
Some people have made the point that digital scopes are "sampling" scopes. In a sense, this is correct, but in a more useful sense it isn't. Digital scopes will capture single events that a true sampling scope won't. A digital scope don't need a repetitive signal to display it. My TDS220 is nothing fancy; it's just useful up to 100 MHz and does what I need for troubleshooting, AND it's VERY easily portable, weighing probably less than 5 lbs.
Now I'm not necessarily suggesting that you go out and specifically look for a TDS220, but I think you should look at that family and see what you can find for cheap. There may have been 60 MHz members of that family that would also work perfectly for you. There are also 4 channel versions. Buy what you can find at a price that fits your budget. And get back here when you start working on your 3S and 3T modules. I have several that I've been putting off diving into, and I'll need help when that time comes.
