Sheet music should be available at this link. The first three lines of music are the tune for verse one and two and maybe all subsequent verses with the following exceptions. The next two lines are an alternative tune for phrase one and two, and the last two measures, of verse three. And the last four lines are the tune for verse ten. It's possible that the verse three tune is also supposed to work for verse six as well, with two verses of the regular tune, one of the alternate, and the last verse (odd one out) as its own tune.
Yes, this was collected from Susie Carr Young. Apparently she only knew it as sung in her own family, but supposedly a correspondent of the Lewiston Journal requested it once, so we know it was in tradition at one point. I'm unsure if the Journal ever printed it, though it would be interesting to see it if they did.
I don't think there is really any significant resemblance between this ballad and "The Green Bed," aside from the plot detail of the young man returning with riches from a voyage and being spurned by his former sweetheart. I don't get the feeling that she wants him only for money in this song, as in "The Green Bed." We don't know for certain if she knows about his new riches when he turns her down. It does seem like the meter is pretty similar though, or at least similar to versions I've come across.