Welp, got my first "not sure this is legit," message from a buyer.
I don't know how to prove or authenticate any of these, the best I can offer is that they've been in a storage bin since the early 90s. The amount of mail-order ponies I had indicates (to me) that they we real enough to collect a bunch of stupid points. And as a child, I'm not sure where I would have gotten good knock offs. If you're bidding or thinking about it, and want more pictures before buying, let me know and I'll add whatever I can to the listing.