The only reason these were classed as pistols is because under that wood stalk is a metal frame the same as the pistol and the barrel can be swapped out for one of pistol length. If they were to make a production model for the Canadian market (like Obokash suggested) that had a different frame then they would be a different firearm and get a different FRT and could be non-res. It really wouldn't need much change, just remove the pistol grip handle part of the frame and replace it with a tab of some sort that the the stock could bolt on to.