The R Examiner disappeard some time ago. EASA introduced FCL.945 to allow FIs to revalidate SEP and TMG by experience provided the endorsement is in their licence. Can't find any reference to R Examiners in any current CAA documents. The latest Flight Examiners handbook seems to be missing Suppliment S1 which should refer to Examining for National Licences, Ratings and Authorisations.