I have recordings of the operas 'Sabbataï Zevi, le faux messie' (1953) and 'Le serment' (1954) both recorded from France Musique. If you are insterested I can upload them, as far as I know they are not available on CD.
I would very much like to hear the 'Sabbatai Zevi' opera, which I believe is considered Tansman's grandest stage work. I have a CD of 'Le Serment', as performed by Le Orchestre Philharmonique de Radio France and released by Radio France in 2007. I'm not sure how available that still is, as I had to order one from a Canadian used CD eBayer.