I eventually got a response from DS who have offered me a genuine Honda gasket for my 550 for £20, could they not do the same for you?
Why do you have to pay? They supplied defective part and are surely bound to replace it free of charge.
In my case, they said the only alternative was the pattern part; I guess that means genuine or OEM is not available.
Anyway, the news on Athena sounds good, so I’ll stick with that for now and use the credit I’ve asked for to get something less critical.
I used to think getting stuff from DS was a guarantee of quality and fit ....
older and wiser now!