I have found an assortment of 45's and 90's along with several options for heavy duty straight sections at a local diesel truck repair supply/parts store in my area. The straight sections I have used are "green stripe" hose which I think is a goodyear product. This is also where I buy coupler material by the foot for my Factory Pipe "B" pipe couplers.( The Blue & Red stuff )
Obviously they won't have just what your looking for all in one piece . . . . but you may be able to "build" a duplicate of yours by using straights and bends spliced together with some thin wall stainless or aluminum tubing.
'Crockett