151 mm sitbones are going to be too wide for a 155 mm Jett.
What about a Selle An-Atomica? Or, if you can tolerate a lot of padding, "recreational" or hybrid-type saddles tend to be wider (since the sitbones are spaced wider in an upright riding position).
Alternately - rather than even bothering to measure - try my method of circling your sitbone-print on a piece of paper that you can bring saddle-shopping with you. It's a lot easier to see where you might be sitting on any particular saddle and whether the slope will let it support you or not.
Speed comes from what you put behind you. - Judi Ketteler