It was only the FAA, and thus US-reg aircraft, that had statutory limitations (60 minutes single engine speed) on 2-engine overwater flights prior to ETOPS etc. Sterling were the first, and for a long time only, user of Caravelles across the Atlantic, refuelling at Keflavik and Gander (and, if going to San Francisco, refuelling in of all places Omaha in Nebraska); they also ran them extensively from Copenhagen to Thailand, but that doesn't have so much overwater apart from across the Bay of Bengal. I think they also did holiday flights to Natal in Brasil, refuelling in The Canaries.
Some detail :
https://www.airliners.net/forum/view...42559#p5942923