More literally than on the Dougie MacLean site Malcolm Douglas cited (!)
I find this winter's night long I find it long, long, long I see only a bare prairie and I don't hear a wave coming in there.
Fali etc. .... ...It is a long, long time since I left Lewis.
The time of evening when darkness grows The spirit is often melancholy Thinking that it is far, far from me The place where I would like to go to a céilidh
I am assuming that 'feasga' should read (or is a dialectal equivalent of) 'feasgar' for evening (= Latin 'vesper') and know of no other word "feasga".
Rendering the third line in the second quatrain "Thinking it is a long, long way from me" would retain the equivalence of "fada" to denote both distance and time in Gaelic.