Scott-
The "soup bowl" as you describe the profile shape of the Campagnolo pedal dust cap was used for a log time. I have not seen a pair with an "O" ring seal myself, nor a simplified shape other than from other brands that just happen to fit.
The shape of the dust cap is very similar in all the pedal sets I have, even the later plastic chrome plated caps have a similar shape, a wee bit different as the plastic outer perimeter is thicker at the toothed edge.
Typography on the caps does chamge over time, hard to date, the smaller typography appears to be earlier. The typography on the plastic caps is raised not, stamped in.
Tpyography on the back ot the pedal also has changed over time, later being larger and a slightly extended font.
Removing and replacing the inner dust shield is a problem, I made a tool long ago out of some brass stock on a small lathe to align it and press it in square, looks similar to a automotive clutch alinment tool, only removed the dust shield to replace a race, that was a job in of itself. For normal servicing, I leave it in.
John Jorgensen
Palos Verdes ca