Good to hear Rich. Let us know what, if anything, you might find. I just thought, if the wheel was found in a stream, it's very possible that it 'entered' the water further up-stream, and has been washed down over the years after heavy rainfall. Worth taking a stroll along the banks, upstream, and look in the water itself.
Many years ago, I came across some bits and pieces from a Lancaster crash in the Peak District, which had been washed own a brook, over a mile from the crash site.
Cheers,
Terry.