Great find Tico!! As you know the snake or dolphin buckle was Used in England, but during the Civil War some of these "s" attachments were worn by Confederate troops also. Considering you found it in Texas, you've probably found a Confederate usage!
Very nice!!!Yep you have the tightener there,and do have one more piece,you dont usually see the tightener posted as I dont think people realize what they were!Good job!