Dixie would be an interesting choice, although the black face routines in the movie would turn off many viewers today. It is a good movie with Bing singing Sunday, Monday or Always and Dorothy Lamour, Marjorie Reynolds(another underrated actress) and Billy de Wolfe are all excellent as the supporting cast. It was actually released a few years back as a Region 2 DVD by Universal Hollywood Classics and Simply Media. I have a copy of it. Lady In The Dark would also be another interesting choice with Ginger Rogers in a different type of role than one she normally would do.This thread is very helpful but depressing lol, since 2 stars with a "No" automatically eliminated the obscure titles I had most hoped for (DIXIE - Bing and LADY IN THE DARK - Ginger Rogers.)
Still, I hope the list yields films with Fred Astaire, Francis Farmer (a Paramount leading lady) and Fred McMurray.