This 1966 Gibson Barney Kessel Regular is the only one I've personally seen with a factory original walnut finish, although I have heard that there is at least one other out there.  The model was only very, very rarely made in colors other than the standard cherry sunburst, I would estimate less than 1% were made in an alternative finish.
 
This example has highly flamed maple laminate construction with a mahogany neck and rosewood fretboard.  The action is low an fast, and the bridge has room for adjustment either up or down as the player prefers. The frets are in good condition with lots of life left in them.  The neck has the typical slim taper, C-shaped carve of the era. The original electronics with the patent decal pickups sound fantastic, and allow for great versatility, think kind of like a long scale, double-cut ES-175.
 
This particular example is in all original condition with the possible exception of the bridge saddle whichis an era appropriate compensated rosewood version.  The model typically came with an ABR-1.  I can't say for sure how this one left the factory.  The finish is in very good condition with very little lacquer checking.  There are some surface scratches.  The only thing that goes through the finish is a small (3-4 mm) chip on the back of the neck.  The chrome finish of the pickup covers is in very good condition, showing little wear.  The tailpiece shows light patina.
 
Weight - 6.9 pounds
Nut width - 1.61 inches
1st fret depth - 0.82 inches
10th fret depth - 0.99 inches
Scale length - 25.5 inches
Neck carve - C-shape
 
Comes with the original hardshell case which is in beautiful condition.
 
Ships free in the United States and for reasonable rates worldwide.