About 30 years ago, I went to Washington DC and walked around the Air and Space Museum with a wonderful tour guide who, at the end, announced himself as the project director for the American side of Apollo-Soyuz.
Did you check out the Astro Space Stamp Society?
http://www.astrospacestampsociety.com/index.html I'm not a member but I was thinking of checking it out one of these days. Anyway, welcome to the Stamp Community Family. Ask away!