Thanks, I just called and ordered the 5 pack.
My dealer may have changed the oil as well. I found almost nothing in it, or in the screen, or on the magnetic drain plugs. Nothing metal anyway, I'm still puzzled about that piece of string, and wondering if there is anymore in there. I don't think it would fit through the oil pickup screen, but if it were already up in the engine, it looks like it might be able to plug up an oil passage.