Can I get an iPad unlocked?
Short => So far, it's not possible at the Moment.

There are some Fake Unlocks for an iCloud Activation Bypass but if I'm correct - this are not working solutions. 

You have to be careful, if the Seller doesn't even know the iCloud/ApplID Mail (normally you don't forget a e-Mail uh?) - otherwise he would be able to reset Password via Apple

Note: Not sure if an iCloud unlock would even be legal in every country!