It's a casual tweedy jacket. Depends a little on the weight and composition, but how about a solid knit, silk or wool or cashmere, in black or charcoal or blue. Or a solid challis, or a madder, but if patterned watch the scale. Something with a bit of texture but generally not pattern unless fine like a herringbone or puppytooth. Stay away from neats. Repp or bar stripes at a stretch.