SGB, the Smith semi auto scattergun was designated the model 1000 and manufactured for S&W by Howa from 1972 until 1984. Depending upon condition they are valued up to around $375. They are, in my opinion, an excellent shotgun and well worth more than the price they demand. While not really considered rare you will not see them often, particularly in good conditon. For some inexplicable reason nearly everyone of these I encounter looks as though ut has been used as fense post.
TFL End of Summer Meet
, August 12th & 13th, 2000