Why does it have to be an examiner in the first place? Why not the FI or CRI who signed the log book for the revalidation flight? They could complete the paperwork at the same time, if the hours requirements have been met, or later on when the required flying has taken place. I always check pilot's log book, licence for revalidation and medical in date anyway, as a reality check for the pilot, you'd be suprised how many are grateful for that!
TheOddOne