[paulsherwin]

The tone correction cap is usually a 1kV component as very high voltages can occur across the transformer primary. That's why I assumed your 1.6kV ceramic cap was a replacement for it. I don't have a circuit to hand so can't refer to part numbers. Can somebody clarify what C66 is doing?

I'm not a historical purist when changing caps and just buy generic types from CPC or Farnell. They are very small and unobtrusive, normally being coloured grey or white. Many people do like to use axial caps that look more like the originals though. Functionally they're exactly the same.

As a general rule, ceramic caps are unlikely to fail.

If you change the 5uF discriminator electrolytic, take care to wire it correctly. The +ve connection goes to the chassis, which is the opposite of what you'd expect.