OK, thanks! I'll strip it down and look for all those things.

Whoever did whatever they did made sure to maintain the 22" overall barrel length as measure with the bolt closed & a cleaning rod down the muzzle. I have 2 such "carbines" (muzzles pictured, not perfectly lined up but both 22").

If there is anything to deduce from the front sight please do. The piece in question is at the top in the 2 barrel pix. The blade is aftermarket, installed by me (original was missing).

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