You can exploit the "maximum copy" and the "duplicate" drop down option in the catalog screen to achieve what you want.
The trick goes like this:
1. In the master server host properties, set the global maximum copy to 2. No service restart needed.
You could change it back to whatever value you had when this is done, if it isn't already 2.
2. Go to the catalog screen, change "validate" to "duplicate".
3. Set the criteria/range for the images you are looking for, BUT, select "copy 1" so you are only going to search for the copy 1 of the images.
4. Search and Voila! You will find that all the images that already has a copy 2 would not appear on the list.
To verify step 4. is correct, you can always change the drop down from "duplicate" back to "validate", leave everything and the "copy 1" setting alone. You will find that the images that already has a copy 2 will appear again on this list of copy 1 images.
They appear again because you are now validating the existence of the copy 1s, instead of trying to duplicate from them.
If you try to duplicate from images that already has a copy 2 (by selecting the "duplicate" drop down), the "maximum copy" setting will prevent you from doing so by hiding the images that already has a copy 2 on this list of copy 1 images.
The reason why you have to set maximum copy to 2 is because, if you set it to anything higher, for the images that already have copy 1 and copy 2, Netbackup will allow you to duplicate from the copy 1 to create a copy 3, which it will do so by not hiding the images that already has a copy 2 in step 4., making this trick ineffective.
Hope it makes sense. This is the easiest built-in way of achieving what you want. Give it a try.