I own one. It’s on a shelf in my den. Got it from a retired dentist friend of the family. It’s been in every halloween display I’ve had for over 20 years.
When I was active in the SCA, I’d dress viking and put it on top of my banner pole. It was fun to watch big, tough guys freak out when I’d convince them it was real.
Palate dimensions, probably.
Cool! Can I have yours when you’re done?
mamakat, was there something about these graves (apparent age or some such) that ruled out the possibility that these were missing murder victims? 
Even if possession of the skull is not illegal, it seems like it might be reasonable to run these bones past law enforcement just to make sure that they’re not evidence of a crime.
So, now that you got the skull situation all figured out, you should check to make sure your house is not built on Indian burial grounds.
You can occasionally buy a kapala in antique stores.
I don’t know, maybe. I don’t give my skull to just anyone. I’m sure lots of other deserving people want it.
Or, in case you happen to be a science teacher, I do know a professor of archaeology who intends to have his skeleton made into a teaching specimen.