Some popular websites that offer free downloads of the Buddha Bible in PDF format include:
You might find a PDF titled "A Buddhist Bible" by Dwight Goddard (first published in 1932). This is likely what your search is picking up.
Unlike the Bible, Buddhism has a vast Tripitaka ("Three Baskets") that varies by tradition (Theravada, Mahayana, Vajrayana). A comparative PDF would likely draw from: