Thanks for the photos! It is exactly the same style of blade as the Stewart Plantagenet:
Attachment 104021Attachment 104022
The fact that you have seen the Ragg original in trade directories from 1840 and I have seen it in a trade directory from 1833 makes it clear that John & William Ragg were the original makers and sellers. As Stewart did not file patent until 1847 that can only mean that he bought the patent rights from Raggs, and the fact that he is listed as just 'patentee' and not 'manufacturer' leads me to believe that Raggs still made the razors for him with his details on the tang.
The clipping below comes from the Great Exhibition of 1851 at the Crystal Palace, and shows that not only was the razor patented, but the process of making it was too, presumably to stop others emulating the shape:
Attachment 104023
Not only that, but even the steel is mentioned:
Attachment 104024
Regards,
Neil