Well, I couldn't find the text to Beeping Slooty, but I did discover that it was the creation of F. Chase Taylor, a/k/a Colonel Stoopnagle, who was an old radio comedian. Here's the text of his Prinderella and the Since, which was published in his long out-of-print book, "My Tale is Twisted". And here's a site all about Colonel Stoopnagle himself. Interestingly, there is a website dedicated to Spoonerisms, in which several people have submitted Stoopnagle's stories without attribution, some as their own creations. So it doesn't just happen with folk songs!

Aloha,
Mark