It wouldn't be terribly difficult to duplicate those trunnions, and even harden them if a material like drill rod was used for the base stock. Drill rod is made "tough" not "hard" so it can be machined to the desired shape, and then hardened by heating, then quenching the part in either oil or water, and there's even an "air hardening" type that's just heated to a specific temperature for a time, and allowed to cool down without quenching. Let me know if you need something like that fabricated.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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