I've just had a thorough look through Google Books, Twitter, Facebook, Ancestry and Newspapers.com.
Not only did I not find the answer, I barely found a single mention of him.
Possible he died off radar, but could very well be alive at 97. Given he served twice in the post and as "recent" as 1989, you'd expect at least one mention of his death to surface.
If you really want the answer to this one, the only option you have left is to drop an email to the San Marino authorities i.e. your local embassy or through the San Marino Gov website. Someone will look into it and give you an answer.