As everyone else has said, this is a great idea!
Since my previous hard-part costuming experience is zero, I'm going to give this a trial run so that I can start figuring out the shapes I'm going to need before I move on to expensive sintra or aluminum.
I checked at the walmart here in town today and they had a khaki colored waste bin that wasn't quite oval shaped, but close. I'd really like a thicker look to the plastic, so I was thinking about getting a muck-out bucket from the tractor supply store and see if it would be possible to cut and shape it. Has anyone found a way to thicken up the look of the trashbin plastic?