WWI Airplane Photo album (sort of) question

[Mr.Jerry]

One of my pickers came in tonight with a pretty well done WW1 airplane & pilot photo album, having both US & German it was really neat, but here is the rub, they were all "pictures of pictures" that is many were famous pics (Quentin Roosevelt, Red Barron, etc) and quite a number I had not seen before but they seemed to be from a set or a few sets of these kinds of photos. All glossy photos,

 

I need to come up with a value to offer him, there were probably 200 pics. Any ideas? My fear is that he thinks these are original airplane photos as $20-50 each.

 

Thanks,

Jerry