Technical Ford Model B Zenith Round-style float

I'm working on a Zenith 124 1/2 carb...as used on Early Ford B's. It is the early style with the round float. Mine is bad. So far I've only found reproduction rectangular 'coffin' shape floats as the late ones used. I don;t think trying to use one of those on a round float carb would work so well as they have different float hinge brackets in the top.

Any thoughts on where to get a usable round float?

 

Zenith part number is D8143.

There was no space for this number in the 1935 version of the parts distributor parts cabinet.

This float was discontinued prior to 1939. The old numbering system was converted to the modern system in 1939 and this number was not converted.

GUESSING your best bet is another used carburetor.