Well, two things. You might try to locate any of the strongman competitors where you live. Odds are one of them makes equipment, ie metalwork. That's where I got mine, from a strongman who was a welder. I don't know if Nova Scotia has a strongman forum but you could always ask on the Ontario board if anyone knows where to get some equipment out your way.
Or just take a picture of a sled you like with the dimensions into a local metal shop and ask them to build it. I can't imagine it costing too much for a bent piece of steel with a post welded to the middle.