My advise to you would be to do what Salty Dog suggested, get a dealer to give you an appraisal. Daniel Moore's company, New Life Art, can also give you an appraisal. Like Salty Dog, I have my Daniel Moore prints covered by my home owners insurance.
What I did was take the certificate of authenticity for each of my prints and dropped them off at New Life Art. I told them I need an appraisal for each of these prints on New Life Art letterhead. I picked up the appraisal and certificate of authenticity for each of the prints a couple of days later. I gave a copy of the appraisal to my insurance company for my policy to cover the prints for the appraisal value. I get my appraisal updated every two or three years for insurance purposes.
Also, somewhere on Daniel Moore's website he has the secondary market value of his prints.
It is important to know that should something happen to your prints, your home owners insurance will only cover your prints at the cost you paid for the prints. It will not cover the prints at today's secondary market value. I've got 16 Daniel Moore prints and I thought it would be foolish to not have them insured.