This is an Optimus Grade with Spangler's name engraved on the bottom of the circle. It is not the Harrison Optimus gun. Hold down Ctrl and + to enlarge picture (don't forget to hold Ctrl and - to reduce it).
This will give you an idea of his dogs and his scroll work as Roger has stated. Now whether Spangler did the Baker-Smith Quality 5, sure looks like it, but I'm not an expert and the picture gets distorted blown up.

Baker-Smith Quality 5

David