Can anyone suggest which figures to use as Baden line infantry in helmet.  Pictures I have seen of their jagers and artillery show a Bavarian style hemet which is quite different from the line helmet, so I can use Bavarians as proxies for them.  Could I use Austrian line infantry in helmet for the Baden infantry?

I would say go with the Bavarians all the way, first the crest is indistinguishable at that scale between the 2 armies, and the issue with the Austrians is that the crest of the austrian is much higher and thinner.

Ray Phillips (ft sumter miniatures)

for the Jägers I guess bavarians would be a good proxy, for the line, why not the Wurttembergers?