[None of these parts have a SN.]
FWIW, Marlin stamps the serial number of EVERY receiver to it's matching stock, when they're fitted together at the factory - so they can be reunited after separation for finishing.
The SN should be stamped into the tang inletting, in the forward end of the buttstock pictured.
That's no guarantee, however, that a particular stock is original to the non-serial numbered parts pictured - only to it's original receiver.
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