Old sprockets or gears (Birstall WF17)

Hi, I’m looking for old sprockets or gears to make some decorations for my garden.
Doesn’t have to be gears, any sort of metal round shape that has interesting patterns/edges will do. I’m thinking 5-30cm diameter range and not too heavy but will consider anything really. A bit bent, worn or cracked is fine - they don’t need to work anymore. And rust is an added bonus. :)
Have car & will collect at your convenience.