To throw in my tuppence worth, I don't think you should go with the original for the following reason. Dubh in gaelic (literal translation black) is quite often used as a word to infer something is bad or malevolant. For example the whisky Poit Dubh, the literal translation is black pot but when the words are used in the context refering to whisky the actual translation would be 'illicit still'.
As such 'Baisceall Dubh' would be more suited to your 'Black Loonies', as in the 'Black' is not a literal description (unless that is you guys are actually all black).
Whereas Dubh Baisceall doesn't make sense to any gaelic speaker, it is just two words thrown together ie madman/loony black