The Poole Harbour course had its equivalent in the Far East in the 60s with a drop into the Johore Strait off Changi, from an Argosy as I recall. I applied for the course, but there was a long waiting list and I got posted away before my name came up.
We had a crew abandonment trainer at Marham where we practised jumping out of a Victor onto a rubber mat. Fortunately I never needed to put these skills into practice, as the statistics for successful rear-crew abandonments from all of the "Vs" were not good, to say the least!