Adding some more pieces to this puzzle, I found another one of these oddball Performa 475s. Pictures are here:
https://imgur.com/a/dGszw
This one came with the original packaging, showing it was originally sold at Best Buy as part of one of those all-in-one-box Performas. The picture on the box conveniently shows the way the system is supposed to look, so I imagine the original owner may have been a little confused when they popped the thing open to discover this beaut inside.
Here's the serial number decode:
Manufactured in: SG => Singapore
Year of production: 1993
Week of production: 30
Production number: 5YL => 6888
Model ID: 1PT => Macintosh LC (Performa)
Your Macintosh LC (Performa) was the 6888th Mac manufactured during the 30th week of 1993 in Singapore.
Same week of production as unity's, separated by a few thousand systems.
So, seems likely to me that these strange critters were early run Performa 475s. I'm surprised that Apple would be willing to let a system out of the factory with such an amateurish looking sticker slapped on for the model. Maybe there's someone out there with a story explaining what was going on internally to lead to this.
Finally, I wasn't aware of it, but there were apparently auto-inject LC 475s as well, albeit with the model printed properly on the case. See here:
http://oldcomputer.info/apple/L475/index.htm
So perhaps these computers were a transitional step during production.