That pin forward of the hinge pin smacks of the Moran & Wolfersperger after-market ejectors, but the mechanism in the forearms doesn't look like the other M & Ws I've recorded. After M & W split up, Gus Habich in Indianapolis continued to offer the M & W ejectors.
These were said to be C.A. Fischer ejectors, though not stamped with all his patent dates --
78539 01 Parker Bros. AH 004 C.A. Fischer ejectors.jpg
somewhat similar --
91964 05 Number 1.jpg
These after-market ejectors show the same circle --
82646 05.jpg
as the #2 forearm --
91964 03 Number 2.jpg
Moran & Wolfersperger ejectors --
73542 02 M&W Pat No. 805.jpg