[Station X]

Before you start changing any capacitors you should make sure that the mains transformer is OK. The cost of rewinding it or buying a new one may well put the set Beyond Economic Repair (BER).

If the lamp is 100W and it glows brightly with the rectifier removed then the mains transformer is pulling about half an amp from the mains, which is quite a lot. The circuit diagram shows a 2 Amp fuse wired in series with the primary winding, but that is for 110V mains. With 240V mains a 1 Amp fuse would be more suitable.

One thing I suggest you do is to snip out or unsolder the capacitor C307 which is wired across the primary of the mains transformer. This may have gone short circuit.

Were the set mine I would power it up using a variac and monitor the voltages on the secondary windings of the mains transformer whilst increasing the voltage.

R301 which you've replaced isn't a cathode resistor. It's part of the smoothing arrangements. With it being open circuit much of the set would have had no HT supply. However it most likely blew for a reason which could indeed be a faulty smoothing capacitor.

As I say though prove the transformer is good before changing any other components.