The EGR valve gastket is available from a Fiat dealer as part number 46773082. Or A Vauxhall or Saab dealer as part number 93178885.
You may also want to consider fitting the swirl plate part number 71751469. It's supposed to keep the EGR valve cleaner. Fiat say if you fit the swirl plate, you also need two ordinary gaskets but I fitted just the swirl plate in my Stilo.
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