Here's my *guess* at the chords in the key of Fmin (for low voice). Hopefully you can transpose it. I guessed at the chords from a piano arrangement of the Ireland version. Since I don't understand chords more complex than a 7th, I just put an * and then explained below the notes played. It looks like one chord in the left hand and another in the right hand...not sure how guitar players name these. If this is helpful, I'll take a look at the remainder. So far this was fun, but tedious.

  Fmin      Ebmin       Bb
  I must go down to the seas again,
  
         Db     Ab          Bb
  to the lonely sea and the sky
  
      Gb    Cmin?    Bbmin   Ab
  And all I ask is a tall ship
  
        Eb       Fmin7    Eb
  and a star to steer her by,
  
          *       Fmin7        **     Eb7 
  And the wheel's kick and the wind's song
  
          Ab7   Bbmin  ***      F
  and the white sail's shaking.
  
        Eb   Fmin        Ab7   ****
  And a grey mist on the sea's face,
  
        Fmin -- acc. very unusual ---
  and a grey dawn breaking.
  
  
  
  * CC EbBbEb
  **BbBb DbAbDb
  ***DbAb FC
  
  

PS My link to the Andrews version at CDnow has changed. Nice to see another Sea Fever lover!