These sg's were manufactured between 1972 and 1974, although some shipped as late as 1979.  Typical Gibson.  Available in cherry sunburst only.  Serial number 050517.  Double cutaway mahogany body, black pick guard, mahogany neck, 22 fret rosewood fingerboard with dot fret markers, stop tailpiece, 3 per side tuners, nickel hardware.  Has two pickup selector switches, one volume and one tone control.  Pretty rare as only 950 were made.  Now for the bad news.  Originally these had mini humbuckers.  Someone has installed full size humbuckers in this one, which means they did route out the pickup cavities a little.  They also replaced the Gibson tuners with Grovers.  We are pretty sure the volume and tone knobs are replacements.  Plays and sounds great.  A reasonably priced rare Gibson sg.