I live on the border to the US, so I've gotten all my tires for previous vehicles with Discount Tire and if I can swap out a spare and bring the punctured tire over to Discount Tire, they will do a proper patch job by dismounting the tire, patching, and remount/rebalance the tire for free. I wouldn't stick a plug into a tire because you have to ream the tire and further weaken and damage the belts in the tire. Too bad the MS doesn't have a place to mount a spare unless you put it in the trunk. With the poor Cdn$ now, I'd probably stick with reputable Tire stores like Kal Tire or OK Tire in my area instead of going over the border.