Single engine LRC would be the correct number. Considering the LR 30-series can only fly on 2 engines for 3-4 hours, depending on exact model, it is a bit hard to see ETOPS being a player. It is not certified for ditching, probably doesn't have the legs to make ETOPS.
What routes are you considering? NA to Europe, most folks go The Maritimes, Iceland, UK. Trans-Pac is pretty much PANC, PAOM, UHPP or UHHH only.
GF