Red George and Martha China Set - Warrented 22k, by who?

I picked this set of china up at a yard sale in Boston for $50. It's a 51 piece set, and has a similar design to the Sabin Industries Crest-O-Gold George and Martha collection. This article talks about it more: http://archive.knoxnews.com/entertainment/life/rosson-this-george-and-martha-dont-hail-from-colonies-ep-411375548-359846881.html

Items in this set include: - 8 large plates - 8 medium plates - 8 small plates - 8 bowls - 8 tea plates - 8 tea cups - 1 large serving platter, 1 large bowl, 1 gravy boat

The problem is that the makers' mark is NOT from Sabin or from Salem Pottery Co. of Salem, Ohio. Is this an early version of one of their marks, or just another smaller company? These pieces go for around $10-15 each, is this set worth $500? Is it worth more?