I'll take a picture tomorrow. I don't know much about the Southern Pen Company. It appears to have been based in Petersburg, VA. Many of the pens are combos (this one is). Someone from Petersburg commented on FPN that there were several "assemblers" of pens - like Arnold - that were based in Petersburg, and Southern was evidently one.
The pen I have does have a "Southern Pen" 14 Kt Gold Plated nib. And the lever has "Southern Pen Co." embossed on it.
Ross