The fact than anyone could have doesn't mean that all that many did... What David did with several of these in the Sample Slabs book is show 1 example as a type and then provide the information about known examples in the text. For others, such as the Long Beach Treasure Hunt (PCGS) slabs, where we can confirm population from the database and set registry, he listed them separately by coin type and included the pop #s.
I have not seen the slab in the original post before, but I agree with everything Burton said on the subject. To add a little, NGC gave away a holder with a blue bordered label at the 2005 FUN show, advertising that they would make custom promotional slabs for dealers. A few dealers took advantage of the service, with the one in the OP a new discovery. This places the slab around 2005, as all were made in that year (or possibly soon after, I don't know for sure). May I use the photo in a future edition?
Thank you, ddddd. I admit I don't know when the third edition will happen, if ever, but I am continuing to research.