Nagaoka MP50/500 are said to be excellent and are readily available. (MP500 is current production, I think.)
Ortofon M20FL Super and M20E Super are still available NOS.
Who is to say that some of the current production MM and MI cartridges are not every bit as good as the vintage ones, maybe even better. Take a look at Grado, Clearaudio, Sumiko, Soundsmith. Recent manufacture makes those less of a crap shoot in terms of condition.
Ortofon M20FL Super and M20E Super are still available NOS.
Who is to say that some of the current production MM and MI cartridges are not every bit as good as the vintage ones, maybe even better. Take a look at Grado, Clearaudio, Sumiko, Soundsmith. Recent manufacture makes those less of a crap shoot in terms of condition.