My orchestration from the piano score of this polka by Philipp Fahrbach Snr.

I’m not sure what he was smoking when he wrote it. Fahrbach can be a bit individual at times but this is a bit odd. Polka’s normally have a fairly simple structure –

Introduction
Polka – ABA structure
Trio – ABA structure
Repeat of Polka
Optional Coda

A’s and B’s are usually 16 bars long.

The vast majority of mid to late 19th century polkas have this structure including all of the other Fahrbach ones I know. In this case the Polka section is all one piece and unstructured. It works. Maybe

The Trio is just AB and the A section has “O du mein Oesterreich” over the melody but the tune is not from the march based on Suppé … I think.