If that saddle was well oiled, there wouldn't be lighter colored friction marks like that. (When I break in a saddle, not only do I oil it well but I also rub the paste-type saddle soap on all the friction areas).
So I think if you give it a thorough oiling it will darken up a shade or two.
It's hard to tell from photos, but that saddle doesn't look like it's been oiled properly in a long time. Not that I think there is anything wrong with it......it looks like it should oil up just fine. But the "dry look" to the leather makes me think they never oiled it much.
It looks like a nice solid saddle though that should oil up nicely. I hope you are able to get it.