Well, your gun isn't broken any worse than this one, and both can be fixed;
However, having it repaired comes down to a matter of economics, and how badly you want it fixed.
From the pictures, I'd say what you have is a late period (1840/1860) single bolt percussion rifle that could have been made just about anyplace. A guess as to origin might be Lancaster, Pennsylvania, judging by the shape of the butt stock, but that's a generous guess at best. Value-wise, as it is now, maybe 300 bucks or so. There's a good possibility that the barrel was used on an older rifle originally, judging from the deep cut rifling style. Take a close look between the rear sight and the breech to see if there is a name engraved on the top flat.
As for fixing it, it's obviously had a rough life, and consequently having this break repaired by a restoration guy is going to cost you more than the gun is worth.
You mention buying a new stock, but unfortunately these aren't like modern guns, and a stock would have to be made specifically for this gun, which again runs you up well beyond the value of the gun.
About the best bet, is to fix the gun yourself if you're handy with wood and glue. There's plenty of guys here that can give you tips on the fitting and gluing process, and you will have saved an old gun from the junk pile and given it many more years of life!
John
