FWIW,
I just looked at the 38/42's from OTB. IMHO, the stock would not have any finish based on the kits that came in around 2002 and the Amnesty registered 38/42's I've examined. The stock would also have a S/N that matches the S/N on the receiver.
Just observations made over the years. Others have likely seen other variations.
BTW, these are great subguns that don't break parts. Good reliable 40 round magazines that load easy (double-stack, double feed). Must have been quite the subgun in WW2.
As others have mentioned, prices in general seem to be out of control.
Enjoy,
K2