it's very hard to find...I think that makes about the 3rd or 4th one I've seen, in over 10 years of collecting.

I think it might be the first Horseshoe matchbook...notice it's 4-digit phone numbers, and it mentions the Eldorado Corporation. The Horseshoe was the Eldorado before the Horseshoe.

Here's what the inside looks like (this is ours, not the one in the auction...and it isn't our auction; I don't know the seller, though I recognize his ebay name as someone we bought ashtrays from years ago).