Buy a boat if you want cheap. They have some great gas wells in Siberia. So they build gas-to-urea plants next to them and make tons of urea per minute, Try Green was plannning to do it years ago--I don't know how the plan worked out. The Russkies were supposed to auger the urea into the hold of the ship.
Cut out the middle man...go to the source.
It runs about $115 per metric ton.