Hello everyone,
I think a quite strong correlation between dentition size and body size has been observed in modern lamnids.
Since we have several available C. megalodon complete or near complete sets of teeth, I’d suggest focusing on the size of the whole dentition (the largest component of the body we have from individuals of this species) rather than individual tooth height and compare it with the closest modern analogue (not only phylogenetically but especially subject to the same ecological constraints influencing body size/body proportions) would suggest a more secure extrapolation of body size.