Thanks guys,
Thomas has shed his thoughts on it, I think it's def. a re-dial.
Shame.

Stewart

: My understanding is that there are two legitimate shades of
: Calculator dial: dark blue (close to a Navy Blue) and Black as
: seen on the 15s. That cornflower blue, while a beautiful color,
: is likely not original. I have always had a question whether
: there is a possibility that those lighter blue ones were a
: service part.