Parts Identification Help

[Castiron9]

Working on the B.B. and I believe I misplaced one of these exhaust "thingies"...One was on the other side so I suppose that you have one on each side of exhaust manifold..Local parts store said I had to go to dealership???????????Any help would be much appreciated..Like what they are called and the purpose of them..Also posting pictures of two brackets that My neighbor gave me when he saw me working on my truck...I know he had a B.B. also at some time and these brackets came from his parts stash..Are they worth anything and of any use to any one..Thanks.................