purveyor of real animal and human skulls and skeletons for whatever purpose you might have for them including research, art, etc. They also buy skulls, and there's a sister site called skullcleaning.com.
I accidentally found Skulls Unlimited while I was googling a picture of a raccoon skull (don't ask). I find this website rather strange, and I say this as someone who regularly keeps animals bones I find in the woods. You can truly make money off of anything, I guess.
And in case you were wondering, a Real Human Skull starts at around $2,000.