Your odds of ever having to worry about 922r are virtually nonexistent as evidenced by no one who wasn’t already on the hook for much more serious shit ever being prosecuted for it.
Are the American made parts you plan on installing marked as made in the USA? For a magazine, maybe. Any kind of internal small part and the answer is no so I hope you plan on carrying the receipt for your purchase around for the rest of your life.
Further,
922r only applies to the person who assembled the gun, not the person who currently possesses it (for the purposes of criminality, it could still be confiscated). Good luck to the government proving I’m the one who actually assembled the parts and not my casual acquaintance I lost contact with years ago and can’t remember the last name of or my wife who I can’t legally be compelled to testify against.
I’m not here to tell anyone not to do whatever they feel they need to do to feel safe but I’m also not going to worry that the ATF is going to waste their time tracking down the provenance of every part of my SBR when I’m at the range one day.