There are many references to related texts and fragments (most quoted) in Peter J. Seng's 'The Vocal Songs in the Plays of Shakespeare', 1967. However, it's imposible to get precise dates for early copies of related texts, so it's not really possible to find out what the original text really was.Seng reprinted the copy in the Percy Folio MS (c 1630-45). The earliest extant copy (Bodleian) of 'The Garland of Goodwill' is of 1631, but it's imperfect, and the "Walsingham" text is missing from that copy. The "Contented Couckould" dates between 1601 and 1626, but 'Hamlet' is of 1599-1601, so that broadside version is probably not Shakespeare's source.