Radials,
If memory serves, one of the last workshops doing Leonides overhauls was in BAC's Hurn works - right between the 1-11 final lines! They also used to get the odd Pembroke or Sea Prince in for refurb. Maybe someone in Flight Refuelling (or ex-Airwork) at Hurn may have some information?
This link gives some preservation groups that may be able to help you:
http://www.britishaircraft.co.uk/air...age.php?ID=512