Value of Magnum Photographer Ara Guler prints

Hello ,

I had been bought two 50x70 prints from Magnum Photographer Ara Guler , signed and back stamped.
He used these prints at the very last of his book.
What are their value today ? Where can I sell to ?

Best ,

Mustafa Umut Sarac

If you still have them I might be interested in buying those. Please let me know how much you are asking