+1 on the physical Bitcoin idea. It's a fun way to see an "actual" Bitcoin. And it actually looks like it's worth something
I don't think this would serve the purpose of the point that the OP is trying to make. The OP is trying to buy something that you can only buy with bitcoin, however to someone without bitcoin, nor any interest in bitcoin, a physical coin has very little value.
IMO the best thing would be to buy gift cards from gyft while making a point that you were able to get a discount