It looks like a duffle bag cut. It should be repairable. And, the repair could be hidden behind the rear band. Too bad you don't have the missing piece and bands, springs, etc. It also looks like someone tried to remove take down disc in the butt. Those show up on auctions and Ebay so, that's not an issue. I would hunt for a donor stock to get the correct laminate and repair that stock, especially if it is in fact the original one.
Al