Welcome Canuslupus (Wolf-dog?). This HSc was part of the final run of 5,000 HSc pistols at Mauser. It was produced in 1977 and is specially marked to commemorate the U.S. Bicentennial with the Great Seal of the United States. It is also marked with a new serial number series.
In the pristine condition you mention with a box, etc., its value would be in the $500 to $600 range. Of course, if you shoot it that value could be lessened ... particularly since the .380 HSc is prone to parts breakage.
Anything else, let me know.