Dale, These are hard to find as you know.
Back maybe 15 years ago Dave Sylvain (technical director for '33)and I sent the parts and pieces of our respective top iron assemblies for 33 and 34 Master Cabriolets to Oak Bows in Pennsyvania. Making a long story short the guy's there made complete sets of top iron assemblies from the original pieces, incuding the parts that go above the side windows when the top is up. 33 is a little shorter than 34 but they look the same.
This was a lot of work that probaly included drawings and tooling that Oak Bows might still have. I would give these guy's a call to see if they could build them for you.
Chris