I have saved some pictures of 198678, a DHE 12-gauge, 2-frame, with a vent rib nicely engraved with the Parker legend, the reinforced forearm loop, but the frame has the concave area for the dolls head. Unfortunately, I don't have a picture of the ramp.
198678 07.jpg
198678 06.jpg
198678 08.jpg
198678 04.jpg
198678 03.jpg
Does the serialization book show it started life as a vent rib gun?