The PAM328 was the one that released the ZF in decent form, and now I'm pretty sure they're not available.
There were others, SF for example, but this is either worse or earlier.
Although, regarding availability of TD, it is better to refer to TD.
If I were you, I would buy a pam312 and find a separate new style bracelet with SEL for a 1950 case. It would be easier than looking for a PAM328 today.