Came across this thread when doing some research on the Belfast.
As I understand it, the reason the RAF only received ten of the original thirty aircraft originally ordered was that the US insisted that we buy C-130 as one of the conditions for monetary support during the 1965 Sterling crisis.
I'm not knocking C-130 - great aircraft and have spent many terrified hours in them waiting to jump out - but if we hadn't been obliged to buy them, what were the RAF planning on using as a para-dropping aircraft? The Belfast has no side doors and the rear door cannot be opened in flight - so unsuitably. So what was the RAF plan at the time?