1966 Valiant Stereo?

Any 65-up A Body knob-style radio will fit. You should be able to pick up a cheap unit from a member - try Cosgig for example.

For my Dart wagon I bought a non-functioning A Body AM/FM and had it converted. Bought another non-functioning AM/FM and will have it converted as well, but to European-spec frequencies, to go in the Barracuda, which is going to my oldest son in the Netherlands.