[drcy]

It's still hard to tell from the bigger image. But I can tell you that if it's a modern computer print, it would have a multi-color dot pattern under a microscope. Also, a black light will help identify if it's made out of modern material.

The picture of Clarke could be vintage, but, if so, I don't know where it comes from. It looks more like vintage in your bigger picture than in the small eBay image. If it is real S74-like cloth, I've never heard of a modern forgery on such material. I don't know why someone would use silk to make such a forgery. If it's S74-like cloth and has genuine foxing on it, I would assume it's vintage. Though some may say the next question is if the picture and the mount/frame are original to each other.

But, without having it in hand, its still idle speculation for me, and I'll leave it at that.