If you're HF and RF only you're mainly interested in periodic signals so any 100MHz scope will do the job. That will allow you to see some distortion without costing too much. Rigol DS1054Z if you want a new one. Any Tektronix analogue scope that works (4x5 series, 22xx, 24xx, 26xx series) which is second hand and tested working with at least 100MHz bandwidth is good too.
You don't need a lot. The digital scopes mainly come into use in non-repetitive and slow signals which there aren't a lot of in RF work.
Very true; see the aphorism in my .sig
Didn't see that - I agree!
(well the half of me that doesn't have TEA does
)