IMHO you should get rid of the clear hose and replace with metal, cheap, durable and no worries of dry rot.
Though I can not help you with a part number, you might consider checking LMC or Classic Parts Of America for replacements. You can probably get a whole kit for your truck. In my task force there is only a 6" rubber section between the cab and the frame. I got a replacement rubber section from classic parts and the rest of my lines were replaced with 5/16- copper/nickel I picked up at advanced.
