Been in contact with the guy selling this gasket and he says that it was found amongst items stored at Ballamys garage in Worthing. He helped the owners clear the workshops before they were pulled down about 2 years ago and the gasket was found with other Lancia parts which have now been lost!
The Dilambda it was bought for belonged to the founder of the business who lived in Worthing. I remember the garage but can't recall whether or not it was a Lancia agency.
He contributes to the forum on the classiccars.com site and one of the guys on there said that his boss would be interested in it as he was building a rally Fulvia and his dad owned the ex-Mike Hawthorne Aurelia. Now I wonder who that might be?
Robin.