I also sing a mix of Nic Jones/Christy Moore/original Child text with the afore mentioned ending.. I still think that tune was written by Nic Jones or a trad tune modified by him. I'll check my record cover when I get home this evening.It's interesting that Child doesn't mention Matty Groves (which is an American version of Little Musgrave and Lady Barnard) among the versions he published.
No sign of any Irish version though.
Cheers, alan