Hey Craig    It sounds like a good one 1st generation japanese. Need more info as to construction, solid/laminate??? etc.   12's generally don't fetch as much as 6 strings but given it's age (70-79)( serial #is low so it wiil probably be 75 or earlier). I'm thinking between $300-$400 subject to inspection. If anyone else wants to jump in here giddyup. I own a 1st gen dr -7 6 string (not for sale) and i have seen them go for up to $600 mint on ebay. A good guitar if its structurally sound.

Neil