I would strongly caution against grafting an extension on to the end of your stock - everyone I've ever seen looked God-awful! A slip/lace on pad, if it gives enough length, is a good answer. It gives the length you need, and leaves the gun original should you need to sell it later. You can cut a narrow wedge & put it under the pad to change your pitch, too.
Another answer is to cut the end of the stock off just enough to give you the pitch you want, and put on a 1" recoil pad, like a Kick Eez or Limb Saver. You can always add some black plastic spacer for length, if needed. If you get much past an inch, though, the black at the end of your stock doesn't look much better than the glued-on extension.
