A few things to consider when selecting probes:
Check the probe's compensation range against the input capacitance of the scope input.
For work in tube circuits check the max input voltage spec of the probe. Also consider how safe the probe is for high voltage circuits.
Lastly consider the attenuation of the probe against the v/dev range of the scope against the voltages in the circuits you're working on.
The Tek P6006, P6008, P6009 should be considered. The first two are 10x. The latter is 100x.
