Fitters: What seatpost do I need?

I’m having trouble finding the right seatpost. I need a 31.6 seatpost that will give my road bike a steep ST angle. My LBS told me if I use a shim on my Cannondale SuperSix that I would probably crack the frame, so a Profile fast forward seatpost is out. The LBS recommended a Thomson since I could flip it around and the saddle would still angle down, but this will only get me 16mm.

What other seatposts out there can get me at least 25mm and get the saddle level? Anybody have experience with flipping the Ritchey TT?

The bontrager race x lite seatpost is flippable. Although I am not sure if it comes in 31.6

The race face cadence is flippable, I would assume the higher level ones of the same design are as well and they come in 31.6

Thanks Kevin, the Bontrager is the best option yet. 31.6 diameter and 20mm of forward offset.