I guessed it might be a Belgian-made gun. It sounds like it might be nice enogh to restore. There are several small shops around that do restorations on nice SXS doubles.

" It seems very difficult to impress most reloaders with the fact that every rifle is an individual, and what proves to be a maximum load in one may be quite mild in another, and vice versa." Bob Hagel, GAME LOADS AND PRACTICAL BALLISTICS FOR THE AMERICAN HUNTER, 1977