The trouble is that a title can refer to two (or more) tunes. -- One Scottish, one English, for instance; which MAY be related, but probably of different dates. Anyhow, the "English" trad tune for "Waly Waly" might be the one collected by Sharp, I think, back around 1904 or so, ageless because truly traditional. There's a whole complex of songs gathered round this. Sharp called the song he got "Waly Waly", seeing a resemblance to the Scottish text in Orpheus Caledonius (1725). But his tune is not the same. "Bonny George Campbell" is a similar case--no way to date the tune unless one knows how it goes, and I've heard at least two. "Bunessan" was dealt with on this Forum not that long since.Ditto for "Wild Mountain Thyme"--as far as I can see the modern tune as sung by the McPeakes is a good variation on the old one for "Braes o' Balquhidder".