To be honest the roads in the area are not very good(being polite)
So even with a railhead at some place on the west coast would not help much
My sister & mother live in a small village just outside Tywyn
And it takes just as long(can take longer ) than the train to drive to Shrewsbury & that's in a car not a HGV.
My sister has to take my niece to Bangor & it takes well in excess os three hours
I don't think pushing freight onto rail will save enough to warrent the excpence.