Quote:
I'm going to have the stamp certed.
I think on balance that is your best course to sell the stamp with the least risk. I never managed to own a #39 when I had a general US collection, but I would have bought a faulty or repaired one with a certified genuine cancel at the right price without hesitation. Like #79, you'll never find one of these without faults (I think I remember seeing one offered at a Siegel sale with clean cert many years ago).