This is a Smith Corona Silent #5A 991554 which puts this as a 1963 which was near the end of the run of the 5A machines.  Smith Coronas, and the 5 series specifically, are known for their ruggedness and dependability and this one's a beauty.  This year had the colors seafoam green and alpine blue.  I have seen this color of machine called both online, so use your best judgment.  I think it is more blue, but it definitely has some green in it, leaning towards aqua.  Regardless, she's a looker and a typer.  The machine comes with a new ribbon and is ready to go.  Free shipping is in continental US only.  Item is cross posted.