I went back to the source posting of the image. It was shared again recently. The original post was eight years ago. No other images.

If someone paid GBP32,000 for it, I assume the providence was established?

I too had a good look at the rifle in the Selous picture. It does look a bit different.

If it was a Gibbs, was it reported as a .256 or a larger cartridge?

The other possibility is, is the rifle a photograph actually an H&H?

I trust less and less on the internet nowadays.