I was thinking that the Baccus Seven Year War British Grenadiers (SBR02) might work as 1796 Austrian infantry (vs. Bonaparte in Italy) if I filed down the tops of the grenadier's hats/helmets to make them shorter and rounder. Any suggestions as to a better plan? 

No, but I dearly want them. What a campaign, ideally suited for 6mm but no Austrians.... 😩

I've painted up a fair number of 1796 Austrians - in both 15mm and 28mm so I am familiar with how they look. But now I want to play larger battles and campaigns where only masses of 6mm will do. I am pretty sure the Seven Years War British can be modified fairly easily and look good. I'm going to order a pack and paint them up and we'll see. 

Mollinary: thank you for your input.

Had a look at the Belgic shako on line. It is a stove pipe shape. The Austrian hat of 1793-1796 is basically a short shako ("pillbox") with a "false front.". I've ordered the British Grenadiers and after I've modified and painted them I'll make a decision. But, I'm still hopeful.

Hello Again Mollinary. I went back and had a better - longer look and saw of course you are correct about the Belgic. I think the pictures I saw showed only the front. Anyways the Belgic is a good substitute as you said. And the rest of the uniform is a good match for the Hungarian infantry. Thank you for the tip and for being patient with me! 

I will test both the British in Belgic and the Seven Years War British Grenadiers. I may end up using both: the Belgic for the Hungarian infantry and the Grenadiers for the German infantry.