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The composition is definitely in the public domain, including in the US. Different recordings of it, however, may still be under copyright.  So, yes, you should look to see if you can find a recording that is confirmed as being in the public domain.  I know that, last year, once the composition went into the public domain, a few people recorded new versions to be used in the public domain, so you might be able to find a recording that has been clearly set up for such use.