You didn't say who this post is in response to or quote any part of the
original posting. After 17 years, I'm not sure that, even if the person
is alive and still reading the group, that he would remember the posting.
I think that if any of us has access to scarce documents, we should try
to take steps to preserve them. You might, for example, make high
resolution scans or photographs of the map and any other documents your
friend has and email them to relevant museums and websites. Ideally, I
think we should also try to get explanatory material about the
documents, telling what they are, where they came from (their
provenance) and what they mean. Perhaps you could get your friend to
write or talk about what the documents contain and give any other
information that he remembers.
Thanks.
Alan