That "Druid" group has as much to do with ancient Celtic paganism as the Knights of Columbus have to do with discovering the New World. (or as the Freemasons have to do with stone-cutting).
Make your own. Draft Traditional Hymnbook might give a start. It will take several years and drive you insane but in the end ... well, I have yet to get there myself, but I'm hoping the end bit is good.
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