Just put some helicopter tape on there. You won't wear through that, and if somehow you do you can just peel it off and add a new piece.
Or, get some of these stainless pads -
Home - Wear And Tear Pads. They are very thin and pliable, will never wear through, and weigh a whole lot less than a steel pipe. Plus, you won't have the cut edges of a steel pipe cutting into your chain stay.
SMH on this one.