Well there are many ways to reduce or get rid of moire. It usually works better with the full size image, but I used one of the typical techniques I use to fix yours. Here is the result:
My fix is on the left, and your photo is on the right. I didn't try to fix it all the way, because the shot is too small and if I pushed it too much I'd loose other qualities. But I think you can see the difference just in the example.
How to do it?
1. Convert the image using Image | Mode | Lab Color.
2. In channels palette select the a and b channels.
3. Then select Filters | Noise | Dust and Scratches
Here is combined screen shot at this point:
Leave threshold at 0 and adjust Radius to remove the moire.
4. Convert back to RGB mode.