I don't think this one is authentic. As you said, having a PSA doesn't guarantee its legit.
He always signs with "Little Steven", often added with "Solidarity" when he`s with the E street Band. (Earlier he signed with "Miami Steve") He may be signing his whole name when signing Soprano or Lillyhammer-stuff. I will paste in my own "Little Steven" below, the clue here must be "Steven". The one you show from Ebay does not look anything alike in my opinion.