M paint code-'68?

[mikeys toy]

I just bought a '68 Valiant and it's a reddish copper color and a paint code of "mm1"
I've never seen this color and am wondering how rare it is?

 

[Ratman1956]

The color is called Turbine Bronze Poly.
Not sure how rare it is but I had a 68 Plymouth Satellite in that color.