I'd offer the pipes that are on my parts car, but living near Buffalo for the last couple of years of it's life, the pipes may not be usable. If you send me an email to m735is at yahoo dot com, I can send back pics of what I have. I just have to finish removing them from the manifolds.
I'm not sure why the 733 uses the flex section. My 735 doesn't have a flex section, nor does the magnaflow replacement. Can your muffler guy use the flanges and go back from there? Or even just make new flanges?