Dan,
I just realized I ignored part two of your question…and now I can’t find your question at all!
Yes, employee service pins are very hard to find, a complete set of five like Stout has on Ebay now is very hard to find. I bought a set of five 15 years or so ago for two grand, so the ones listed now are a steal. Stout sold a couple individual pins at auction a few weeks ago for over 2000 each.
You are correct, the items listed appear to be from a large collection, as the pins, prototype and 6414 with brown autos are all uncommon items.
Hope this helps and good luck.
David Doyle