Thought I knew it all when it comes to O scale figures, but I learned a thing or two from this thread. The 3D scanned are definitely the most realistic I have seen, but also the most expensive. I knew Scenic Express had figures, but didn’t give them a good look till I saw this thread. I might just add a few to my next order.
In my opinion, Artista is the best compromise for realism and expense and they do have quite a variety.
Barclay Company classic o scale is another source and MetalFigures.net which is usually at York. Web site does not seem to be available at this time.