Good eyes Kurt! I just went buy what the seller stated...
"I am selling a complete 1969 DZ 302 engine that I purchased on E-bay about four years ago. It has been in dry storage since I bought it. The motor was purchased with the intention of installing it in my RS/Z-28 but have found a better match for my car. The long block was rebuilt by a reputable machine shop in the Seattle area. Block is a 3956618 casting dated B139. The stamp pad reads 19L521002 VO219DZ."
Paul