I believe you can get one from Haspel.Living in Atlanta I can appreciate the appeal of light and unconstructed. But previous commenters are right. The cut is appalling
Years ago I owned an unlined and unconstructed seersucker blazer in solid navy. It was one of the most versatile garments I’ve ever owned. It is hard to find solid navy seersucker jackets, and even harder to find them unlined and unconstructed.