A Honda dealer sold me the more expensive o ring chain for my Cb550, as well. When it ground on the case I took it back. The counter salesman insisted it wasn't a chain problem, so I asked him to consult with the service manager. The service manager was well aware of the issue and confirmed that CB550s can't use a 530 oring chain.
The salesmen refunded the difference between the standard 530 and the oring chain and exchanged the slightly used part for the standard chain.
I've since learned that the front sprocket can be milled and a spacer added to provide the needed offset. Technically, this would put the chain out of alignment, which is probably workable given the small amount needed.
Of course, a 520 oring chain is about the same width as a standard 530. But, you have to change both front and rear sprockets as those are narrower than the 530 sprockets.
Cheers,