According to Brian Rukes book, the serial number range ran from 124420 to 147568. He has production history for 1963 as follows:
     Model 1600, series A ......serial # from 127044 to 137709
     Model 1600, series B .....serial #  from 137710 to 140262  
He lists total production numbers as being unknown.
              Well, this isn't a lot but it will give you a little something.
                                       Cal