It reminded me of a Conn, so I went looking. The Pan American 58B
has a lot in common with your horn. Take a look.
The Conn Loyalist
Conn sold the Pan Am line to many, many outlets. Yours could be a Pan Am stencil with some after market adds. Does the serial number begin with a "P" ?
That pinky ring "C" also reminds me of the type of stylized bracing used on Conn saxes from the mid 60's on.
Then again, it might just be some companies copy.