I purchased a boxed 1 1/8th one off ebay that arrived in its original box. On the packageing there is a tick box to indicate diameter and it lists both 1 1/8th and 1", So I assume at least that they did.
You could however get a 1 1/8th and shim it to fit. Infact if your interested in a gunmetal one, I may be able to do you a deal as I decided it didnt look right on my Roberts after all.