It's actually metal tubes and the verticals have a rubber padding of some sort over them. Of course they are pure shit as usual from LR. Mine was dented by the PO and was rusting out.
I searched for a replacement for years and could never find the A-bar version, only the full brush bar or the chrome version. I saw one on ebay once but it was purchased pretty fast.
I think the new owner of my truck may have had someone replace one of the tubes.