It's probably just a well used brush, or a unique grain on the wood handle, or just an older version, the written label might have even worn off.
If he says "Raphael 803 squirrel mop", and you can't see any marking, that is probably as close to knowing what it is. Even though the spiral grain is distinctive, it mostly matches the simple wood handles they come with. From what I can see, it's just a quill brush with a very plain wood handle, not even stained.
Its still clear it's a squirrel mop, probably higher end like the Kazen the 803 is made out of, so if its not exactly the Raphael, any squirrel mop will likely do.
You can get these cheaper, real squirrel but probably not Kazen, with the Jackson art supplies house brand brushes, these also have plain wood handles. The Raphael are a premium brand for brushes, not cheap.