Politechnika Cube Painted
Answer from the Politoys factory (2002):
Yes, we produced those purple Rubik's Cubes that you are looking for. They were made around 1980.
We tried to print the colors instead of using stickers but the orange paint disolved the black cube and turned purple. We only made a few of these.
We used completely square stickers around 1978.
An interesting fact: the first Cubes were twice as heavy as the latter ones.
Istvan Dupai
POLITOYS