That's a "Macintosh" sticker on the face of that Mac in the EBAY auction. You can see how the right side of it is reflecting in the sun. The real question at this point is, WHY put that sticker on the front of the Mac? Seems odd to me, but certainly nothing that leads me to believe there is a HyperDrive inside.
My 512k with internal 20MB Hyperdrive also had a sticker on the face of the Mac, but the sticker was old, cracked and falling apart so I removed and placed it into File-13. Thankfully, the Mac wasn't yellowed hardly at all so you now cannot tell there ever was a sticker there. But I remember the sticker well, it was not the flat kind of sticker as shown in that HyperDrive 2000 photo, nor was it exactly like the other sticker you link two (with red it in). My HyperDrive sticker was about the same dimensions as the HyperDrive 2000 photo sticker, but mine was not perfectly flat. It was -- how can I describe it -- like it was encased in a transparent plastic "bubble" or "dome" of sorts. You know the kind, they leap out at you. My HyperDrive Mac also didn't have any special sticker on the back of the Mac either.
Even so, with EBAY you never really know what you are going to get. Who knows what is lurking inside that old Mac. And in many cases, if the sellers knew, they would try to charge a lot more.