The Japanese Manufacture a Tractor Model for Rice Paddies

The Japanese manufacture a tractor model for rice paddies. They are smaller than most Canadian tractors and perfect for a weekend farmer who wants to tend to a small garden. The tractors are not sold in Canada through any authorized channels, yet they are available in Canada at prices below the manufacturer's suggested retail price. What is the term for how these tractors are being sold?

A) Under the counter
B) Over the counter
C) Through globalized channels
D) In the grey market