That is an easy fix, and I have fixed many of them...take the stock off and very gently spread the crack, apply some two part clear epoxy or glass bedding compound like the red box Brownells glass as its more of a liguid and then hit it a lick with a air hose if you have one then apply a tad more and using a large rubber band or some small surgical tubling wrap it up, let it cure then lightly rub it out and match the finish..be sure to clean up the inside also..The wood there is too thin to pin and really no need. I also go ahead and glass bed the butt stock as long as I'm already there but thats another project.
