Since the last posting I made, I have contacted the VA for help in trying to determine the dates (within a range) that the stones were made. They have replied wanting pictures, and saying that they were turning it over to their historical dept. I sent them pictures of the different types of engraving, and even the variations of the stones. They also said it may take 2 to 3 weeks to get all the information together to give us an answer. I will post as soon as I get that information. Also I did find out that there are several different companies in different states that are producing the stones now.
I questioned the quality control issues concerning the different measurements of the stones, so maybe they can answer this also. All of this may not mean anything, it just got our curiosity roused up, it will be most interesting to see what they have to say.