For Derek Bell (of the Chieftains) - enter "Derek Bell" under Popular Music (!) in Amazons, and you find a page, with this and others. Carolan's Receipt would be my choice - but there's others on the page that would probably be as good.
For the Chieftains, I'd be happy sitting in a restaurant where they played Chieftains Vol 4 or Vol 5. Enter "Chieftains" in Amazon (under popular music), and you get a page with those, and many others - but that's me, and your customers might, unacountably, have different tastes.