dunfire got his information from me.....so.....I can tell you that there are three possibilities. #1 - find a locksmith or Chevrolet enthusiast with a bunch of try keys and see if you can stumble across the right key. #2 - have a lock smith pick the lock and if he can get it open and maybe a key could be made. #3 - forget it because 1, 2 and 3 are the only choices you have.
