Perhaps they could add this bodyshell on top?

Look, someone has made a prototype:

...bear more than just a passing resemblance to the following fictional snack character?

The answer is the Elswick Envoy:

It may look like a strange practical joke, however the little Envoy was a clever little car. Derived from British Leyland's Minisimma concept, it was based (stangely enough) on a Mini and was designed so that a disabled driver could operate the controls directly from a wheelchair for maximum practicality. A great idea and cunningly executed, in fact there was even a film produced featuring the baby wedge.

However it is William Town's original concept that really hits the spot. It did the rounds at the motor shows in the mid seventies as a possible Mini replacement, yet never made production until the unused design was adopted by Elswick.
Being penned by the same hand responsible for the Aston Martin Lagonda no less, the shape and boxy-goodness are boyhood concept car stereotyping at its very best. You can take your Smart car, Fiat 500 and, obviously your Nissan Joke, this is my choice of city car thank you very much.

I too would wear a white turtleneck jumper just to get one.