Just for the record, I believe the last Belvedere flights in the UK were those of XG455 in February/March 1967. This aircraft had been damaged whilst on the OCU (SRCU, the Short Range Conversion Unit) at RAF Odiham, and was in 2nd Line undergoing a lengthy repair when I inherited it in 1966. By February 67 it was ready for flight test, and one bemused Wessex instructor (and former Belvedere operator) was given a special Transport Command category to fly it. Muggins ("Graham, I am not flying that bl***y thing unless you come with me") went as flight test observer on its first post-repair flight on 15 February 1967, and again on 3 March to swing its compass and cover a few remaining flight test points. It behaved magnificently and shortly afterwards flew to Marchwood military port near Southampton for shipping to the Far East.
Apparently No 66 Squadron at RAF Seletar, the last to operate the Belvedere, was disbanded the day before the aircraft arrived in Singapore, and it was scrapped there without ever flying again.