It's not an M1A. That's a proprietary model name for SAI only. It's an M-14SA, or M14, or variant thereof. Sometimes M14S....
Some of the Chinese rifles were shipped as "M305" and so on. But NEVER as an M1A, which is a copyrighted brand-name based title. Polytech and Norinco ( the old Mukden facility, re-named ) varied the design details of their forged receivers in very interesting ways.
SAI ( Springfield Armory, Incorporated ) suggested that it might be some kind of mistake or violation to call their cast M14 spinoff by the name of the old military rifle. If ATF ever so ruled, no one can locate the evidence. The implication, obviously mistaken, that "any M14 is a "machine gun" was foisted as their cover story at the time.
If one calls it an "M1A" on Federal or some state paperwork, it's an error and can be a violation.
Very nice stock, and yes, worth restoration.
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