I just recently bought two wagner 10 inch cast iron skillets and they are remarkably different. One of them is much lighter and the inside is polished smooth. The lip edges are thinner. The bottom has markings that say "Wagner Ware Sidney -O-" and "1058 A".
The other pan is heavier and rougher in the inside with a thicker lip edge. The back says "Wagner Ware", "10 1/2 inch skillet", and "Made in USA K"
They both have number 8 near the handle