Microdol-X was the standard developer for Panatomic-X. Although it has no cult following what-so-ever, it does produce the most printable negatives from this film. Pan-X is pretty contrasty so the old "if in doubt overexpose/under-develop" advice holds - even more so if it is very aged. Very slow speed films don't loose much speed or gain much fog with age, but 1967 is pushing it - Xtol may be a good choice as it holds film speed. I would stay away from Rodinal, it looses up to a stop of film speed, though it does have low fog levels it won't do anything to mitigate the fog on old film. Age-related fog is best just printed-through.
You may find the ink on the 120 backing paper has interacted with the film and you may get frame numbers in the middle of the images.
You can, however take advantage of the print-through...To make the best use of the one roll you might use it to take pictures of things that you would want to look like they were taken in 1967 on a roll of film found in an old camera. Interesting vintage photographs - very quirky snapshots - sell well and command a good price - here is your chance to forge^h^h^h^hcreate some.