One wonders.
Simpson has two FN Hi-Power holter shoulder stocks listed for sale:
http://www.simpsonltd.com/product_in...oducts_id=2869
http://www.simpsonltd.com/product_in...oducts_id=1710
The are listed as "Pre-War" holster stocks.
A glance reveals that the wood has pre-war configuration.
But the holster is "Post War". Additionally, the holster is attached in the post war manner.
So what we have is a pre-war stock to which someone attached a holster ----> after WWII.
Hardly a pre-war item.