That auction was very likely a seed unit, that someone removed the sticker.
As it's basically a /// Plus with an older style keyboard. They didn't get released with that keyboard on them. But it's the right layout.
The /// Plus has nut plates for attaching the periphery cables where as the /// did not.
The one auctioned is very similar to this one that I have:
No bezel plate on the backplane with port identification markings.
Plain brushed metal base plate.
Original //e color scheme & layout keyboard, except mine has the European keyboard.
No serial # on the logic board (usually between slots 1 and 2)
No system serial number sticker, though the auction listing one has a glue pattern that is similar to the standard /// style sticker. The /// Plus sticker is a proper rectangle, and not missing the upper left corner. That's the sticker that has the arrow pointing at the power supply saying not to open the small metal cover, and the other portion has the system serial # and [ ] 128 or [ ] 256K.
Not pictured, that I got at the same time with this /// Plus are a Disk /// drive that has a generic gray round cable with d-sub 25 pin connector for the back of the /// Plus, a Monitor /// with a purpleish screen overlay instead of the green, and two unused service part packaged /// Plus motherboards.
I've got at least two other /// Plus systems and several ///'s in various condition from hangar queen to working, with one in the matching box.
One of the release model /// Plus's has an Apple asset tag on it and is serial # 6548.
I wish it was 6502
