Because there isn't a single official source, users typically find these tones on community-driven platforms or by creating their own:
The ascending arpeggio after the first chorus (approx. 1:24 in most covers).
"The exclusive version without the background strings is gold. It sounds like someone is playing live in the room next door. Very intimate." –
If you want to play it yourself and record a truly "exclusive" version, use these guides: