Dear Suzanne @sgalligher,
I use our Megalodon Forum as a platform to answer your question about potential other megalodon body parts that might have been found beside teeth and vertebrae. Please do also use this forum for further questions, we appreciate it very much. As far as I know not much else has been found other than teeth and vertebrae. Probably some cartilage fragments but nothing really identifiable. There are some findings with associated teeth where all the teeth were found in the correct place and order but still there was no jaw material left since the cartilage has been dissolved over time. The problem is the size of the Megs. It is much harder for a huge specimen to get completely fossilized since it is more unlikely to completely get covered in a dense cloud of very fine sediments in just a few seconds. That is what actually has to happen to preserve soft tissue or cartilage. But it is not impossible! As you can see with the samples from the Solnhofener Plattenkalk or the Posidonienschiefer in Germany, shark soft tissue was preserved. Another outstanding example is the fossil record of the Great White Shark from the Pliocene of Peru housed in Gordon Hubbell’s collection (Ehret D. J.; Hubbell G.; Macfadden B. J. . “Exceptional preservation of the white shark Carcharodon from the early Pliocene of Peru” (PDF). Journal of Vertebrate Paleontology. 29 (1): 1–13. doi:10.1671/039.029.0113.)
A very helpful resource comes from our friend Jayson (@jayson-kowinsky) and his very nice website:
maybe he knows of some preserved Meg cartilage?
I hope I could help you