I don't know what the iron item is.
I believe that the buckle is
medieval or later. There were a few square or rectangular buckles in
Roman times, but none exactly like this that I am aware of.
The
bell could be
Roman. It matches Nowakowski
type A, which is generally dated to the 2nd-3rd century AD. The
type was used throughout the Empire but also by the eastern Germanic and Dacian peoples. It might also be a later item. I don't know the
medieval and modern
bell forms so it might be later, but it certainly matches a
Roman type.
SC