Hello,
How about some cast members from George Romero's Dawn of the Dead?
Ken Foree, Davis Emge, Scott Reinager, lenord Lies, Jim Kurt, They usually do conventions as a group and are very popular in Europe and the US. I attended the Pittsburgh Dawn of the Dead reunion recently and there was alot of people who had travelled from the UK for the event. Also they attended a convention in Germany recently and it was a great succes. Maybe Tom Savini as well if you can get him to fly