I am aware that both the scope and mount are from the 50s.
The rings are much later. The only thing I find odd is the dummy Lyman sight base which was not intended for a functional slide. Did Stoger offer horn on their stocks? How about Townsend Whelen's company in DC?
I can not tell from the pictures, but what is different about the base as to make it non-functional? Are there just parts missing, or is the base itself machined differently?
It does have a little look of a John Hutton, who was the stock maker at NT&S before the war. To me it looks like it was either refinished or maybe restocked later, possibly when the scope was added. Of course that is all just speculation. I do agree with the others, to me the depression guns used the armory stock to save money. A lot of very nice and expensive rifles were build on NRA sporter barreled actions.
Nice rifle whatever you want to call it.
John