BTW Great track, an old favorite of mine. I think the note being played in C6.
If you want something more realistic Ableton do Orchestral Strings which you can buy, or I have NI Konkakt as part of Komplete which is brilliant, but expensive.
Well, I am sure that the original is an FM synth, not actual strings. And I think Strings - FM Orchestra is pretty close if you play around with the settings, maybe turn the Mod C down and the reverb up and the delay mix up a bit. I think a sustained C6 then maybe F5 then A5 is somewhere in the right ballpark.
If not you could try Operator string snth section.
Real string samples sound too real for this kind of thing.
Like all these things they only really sound good when played with everything else.