My band, Blarney, recorded it a few years ago.

This is the chording we used.

  (Dm arpeggios for 4 bars)
  
   Dm         Em            C          G
  away to the westward, I'm longing to be
                                             D
  where the beauties of Heaven unfold by the sea
                         C                          G   
  where the sweet purple heather grows fragrant and free
                      D             C  G
  on a hilltop, high above the Dark Is-land
  
  
      G                         C           G
  oh, Isle of my childhood, I'm dreaming of thee
                                          D
  as the steamer leaves Oban and passes Tiree
                        C                      G
  soon I'll capture the magic that lingers for me
                       D            C  G
  when I'm home again upon the Dark Is-land
  
  (Dm apeggios 4 bars before next verse)
  

There are a few bass runs on the in there in spots too on the C chord mainly and some Dsus4 hammer-ons. An oft-requested perennial favourite of ours.