Those spacey sounds in the instrumental break were done with a Mellotron and an ARP Synthesizer, both played/programmed by James Newton Howard. Other instrumentation on the track:
Davey Johnstone - guitars, banjo
Caleb Quaye - acoustic guitar
Kenny Passarelli - bass
Ray Cooper - congas, tambourine, marimba (sounds kind of like steel drums, evoking the island)
Roger Pope - drums
Kiki Dee, known for duetting with Elton on "Don't Go Breaking My Heart
" the following year, was among the backup singers along with Passarelli, Johnstone, Quaye and Ann Orson.