I'm with Andy. Why do you need to know?
Not just curiosity, but until we know WHY you need it, it is hard to determine what will be an adequate way of finding out. Just satisfying a question is easy; but if its for legal reasons, then something more formal will be required.
As far as i can tell, there was no recorded transfer of deed in 1951, so unlikely you will ever get a precise value; but you may get an adequate estimate based on recorded information. But even an estimated answer to this question is going to require research, and that will probably cost some amount of money. If it is information that will be needed legally, it will cost more.>
You should ask your agent to find this information out for you in a form that you can use; <and if they can't do so, ask to speak to the broker; and if he can't, then look for another agency!> ;>