John Rhys-Davies twenty years ago, and he would have been marvelous. But he's pushing 60 now, and Caruso was 42 in A Cadenza for Caruso. Too big a difference.
For Marian, an Amy Madigan type would do well, IMO. Madigan herself is a little too old now, I think, but someone like her. Intense and not glamorous.
Darkovan, you started all this. Did you have someone in mind?