Peter, see page 79 of the manual. It has a reproduction of a portion of page 15 from Rostand Mfg Company's Marine Hardware Catalog #20 (their last).
As you know, this company supplied Pierson until the 1970's. The "side lights" are catalog #54, the "stern light" is cat #56 and the "bow light is cat #52. I assume that there is no patent protection on these styles of light fixtures which is why Perko may have something similar. Got photos?