Marion, probably more than half of the tunes named here (including the Carolan pieces and Ashoken Farewell) weren't actually written as waltzes. I think the rules are if the tune can be played so people can waltz to it, it counts.

Margaret's Waltz MIDI.

Try Empty Wallet Waltz (haven't learned it myself) or Southwind (AKA An Ghaoth Aneas), a beautiful slow air that makes a beautiful waltz when speeded up a bit.