These two items are part of an 1855 2-piece buckle. This tongue section goes on one side, and a large circle section goes on the other. They started manufacturing these in 1855 and changed the name of the company in 1856 to "Pollack Brothers" which replaced the "Wetzlar & Taussig" letters.
Normally, these go for around $300 for just the tongue sections you have. But as with any artifact of this nature, it all comes down to what collectors are willing to pay for it.