12" diameter has 90 inches of cutting for one color.  I think you can use laser, fine saws, or a knife for this.  If you cut both sheets of veneer at once, the two pieces would fit together with one cut.  You could use a stain for one color, but you would need to keep the grains from aligning.  Assume it is a yin-yang circle for now.  The details are slightly different. 

First run is 500 units, then 5000