[Arran]

I'm surprised that the audio output transformer is shot but the audio interstage one isn't. It seems that the audio interstage is almost always gone on sets with push pull #45 tubes especially the primary side, at least there is a cheap substitute you can build now with solid state parts, if you can stand having some "sand" in your old radio. It isn't really necessaty for P-P 45 tubes most of the time but some sets used interstage transformers with odd impedance ratios which you can not find stock and would be expensive to have rewound or replicated as a one off.
Regards
Arran