Fossil whale bone (specific bone ID)

[EpicEiniosaurus]

Hello all,

 

So i've recently come into the possession of this chunk of bone, and based on the size, porosity, and locality (York River State Park) I believe it's a whale bone (Miocene-Pleistocene in age, likely a mysticete). 

My question is, which bone exactly is it? It seems to have some fairly distinctive features that seem to lend towards identification, but after around two days of research i'm stumped. I'm thinking it could be anything but some vertebral element, but i'm not sure.

Any help is greatly appreciated.