I usually drill my own. On my current gun, I got too casual, and the rr hole occupied the same space as the front bolt. Hmmmm. after some pondering, I made a dowel of maple, and glued it in the hole.
So now I am going to redrill, but with the barrel out of the stock, I can pull the forestock down to redirect the hole a touch.
Darned if I didn't go too far the other way, and almost come out thru the grip on the forestock by the guard!
With some planning and care, you can get through this job 90% of the time just fine. It's that teensy tiny little ten percent that hangs over my head while drilling that bugs me.
Tom