Mike, A couple of suggestions/ info--

But first, I'm confused about the Four Queens part -- are they marked "Four Queens" somewhere, or was Tom Callahan part of Four Queens somehow? Are these actually black color, or just dark dark red & aged?

1. Info, but probably dead end -- the 2 biggest Dice collectors & historians, sadly, are no longer with us. Jeff Laudeman published 2 big 3-ring binders of his chip catalog with photos. I thought it was in the club library, but can't find it there. The other dice expert that I knew about, a LV resident (can't recall his name, but was active at the chip shows) has also passed.

The only dice book in the club library is nearly 20 years old -- here's link to get it, but I think it's a long shot.
http://museumofgaminghistory.org/mogh.php?p=lib_reserve&b=296&u=

2. Maybe a REAL lead -- One dealer at the June 2024 show describes his specialty area in the convention catalog as "Lots of dice, vintage and recent..." Maybe he could help you? If you have a catalog, look at the Table 51 listing. If not, I won't put his name out publicly here, but email me and I will give his contact info to you via email.

Good luck!