I found lots of C8051xxx had been NRND, which PN should I use in new design?
Try the part that was not marked with NRND.
Also check the longevity commitment to see if it helps:
some EFM8 could be used in auto application. take BB2 as example (it don't naitively support LIN or CAN bus):
C8051F506-AM and other has CAN bus support.