Why isn't 'Marco Polo' on Region 1 DVD and Blu-ray

I remember thoroughly enjoying this mini-series back in 1982 when I was still in high school. Does anyone know why this production is not on Region 1 DVD or better still, Blu-ray? With the 2013 Starz series due to heighten interest in Marco Polo, I hope whoever owns the rights decides to cash in sooner rather than later!