I've also been looking at different suppliers and it looks like the one you ordered off Ebay (seen that one too) have very similar/same dimensions. The bigger ring is same and smaller one is 1mm smaller.
I asked the supplier if this would fit an F30 since in the description it says "F30 style" but its meant for E90/E92/E93/M3. He assured me that it was designed for the F30, but it would also fit in those other BMW models as well.
For $30 it was worth just a try, but he said I would have to order in quantities of 10, which would push it to $300. I need one. I don't need 10. Plus shipping would be another $50 or so. I backed out. Unless there are 10 people here who want to each get one and split the shipping.
Sorry... but I think we hijacked the OP's thread ... oops