If you are not willing to shell out for multi-GHz differential probes, then I would agree that a resistive Z
0 probe is the way to go.
Howard Johnson and
Doug Smith have written about them, and there have also been posts (
1 2) on this forum. Since they are DIY and the components are cheap, you can easily solder them down. Obviously you need a scope with 50 Ohm inputs (or less ideal a feed-through terminator).
If you want a sturdier variants, you can sometimes find used Tek/HP Z
0 probes for under $100 on eBay. Some part numbers would be Tektronix P6156/P6158 (note that it comes with the tip and that the P6156 has multiple tips selecting attenuation) and HP 54006A. These are not made for soldering down; they were designed back when circuits were through-hole.
The logic analyzer connectors are mostly to cram many channels in a small space, but they are good to look at for termination and minimizing stub length. Note the suggested routing for some of them that has the traces running under the connector, creating a minimal stub.
Not sure what the cheap solution would be for differential probing. Probably a used Tek/HP/Agilent/Lecroy differential probe. I can not see CH1-CH2 work very well at these frequencies.
Also keep in mind that you might need much more than 500 MHz bandwidth even for a 50 MHz digital signal. It is all about the rise time of the signal and the probing system. See application notes by
Tektronix and
Keysight with details.
Videos about low inductance probe connections: