A Sousa grade Ithaca should have engraving on almost every square inch of the metal. If you have no engraving, you have a field grade gun.
From your description this appears to be a Flues model produced in 1912. Sousa guns appear to have had a lot of fancy engraving on them. The "S" on the metal on your gun does not stand for Sousa. Judging from gunbroker.com auction prices, your gun is probably worth $350 - $550, depending on condition and how badly a collector might want one.
the book that I haveshows 11 different grades for that serial #. depending on the grade and the condition could be anywhere from $100 for the field grade in poor condition to $15000 for the sousa grade in excellent condition. (source 2005 gun digest guns & prices from krause publications
There is no S12 listed in the Standard Catalog. Only 11 people in the world can own a Sousa Grade Ithaca double. If you have one and have lost the barrels you are out of luck. If it is a single barrel trap gun, the odds are not much better.
the book that I haveshows 11 different grades for that serial #. depending on the grade and the condition could be anywhere from $100 for the field grade in poor condition to $15000 for the sousa grade in excellent condition. (source 2005 gun digest guns & prices from krause publications
Cody Sousa's birth name is Cody Andrew Sousa.
Sousa Santos's birth name is Lus A. Sousa Santos.
The Spanish surname Sousa is the Castilian form of the Galician and Portuguese surname Sousa or Souza.
Lisa Sousa was born in 1962.
André Sousa was born in 1990.
Sousa Dias was born in 1956.
Sousa Santos was born in Portugal.
Jon Sousa was born in 1978.