The standard Mazda R360 came in 3 different exterior whole-body colours:
Colour Option Brochure
Translated Colour Option Brochure
The non-standard Deluxe Mazda R360s came in multi colour variants:
Blue and Cream
Red and Cream
For the interior of the Mazda R360, there was a choice of Red or Blue.
These colour options were available for the seats, carpet and inner door panels.
Source: Mazda UK via Twitter.