Unfortunately there isn't a chance to "update" the die. To make changes would require art changes and a new die to be created, to the tune of another $250.
To me, the point of getting the sample made was to ensure that the overall "quality" or "feel" of the piece was satisfactory to me. The sample came out looking just like the art rendering, and no one criticized the "G", "VR", and "4" when I posted up the art rendering. I was more concerned with the end product being of good overall quality, not cheap feeling, not the wrong color, etc.