where can i get a washer for my gener8 steam generator? ?

i have a gener8 steam generator and it needs a replacment washer but there is no contact details on the manual so i tried a plummers they have the same size but not the same thickness .i tried asking the place i purchased it from but they said they have no contact details so i am desperate with an iron thats fourteen months old but can not be used all for the sake of a rubber washer.