Are you sure you/he mean/s "thousand metric tonnes" and not "thousand metric kilos" ?? A thousand metric tonnes of sugar is quite a lot ...

And how does he want it delivered? 12 thousand metric tonnes of sugar is 12 million 1kg bags. Does he want it in bags? Or loose by the trailer load?

A quick search suggests that in the UK, Pheonix (sic) Business Ltd will deliver a minimum order of 12500 metric tonnes for you. Briz Trading Company will allegedly deliver as little as 125 metric tonnes. http://briztrading.com/en/sugar

There are more, hope that helps.