Good idea. It’s a 3837004 casting. Which (from Tim’s site) makes it like a 55-57 235 block.
It’s a FB ad and the engine IS attached to an automatic transmission of some sort, I assume a PG. But that alone wouldn’t make it very “special.”
Edit: Here’s the FB ad link if someone wants to take a crack at decoding the serial number.
https://www.facebook.com/share/16o16huYnr