The .300 Savage would be an ideal fit for an M98 Kurz / short action.
I remember having seen in this forum some Mauser Kurz rifles with .250-3000 caliber, but can't say if they were original (again for export only) or rebarreled / reworked in the US.

In German catalogs BEFORE WWI I see quite some US handguns, rifles (Winchester, Savage etc) and ammunition.
But I think BETWEEN WWs I and II there was very little import or none at all - a lost war, economy crisis, and at some times import barriers.

I'd second what Kuduae said - before WWII there wasn't any .30 caliber hunting cartridge in use in Germany and Austria. And if you want to use a .30 barrel, you might as well chamber it for the .308 Winchester which will be not "period-correct" but otherwise a sensible choice.

fuhrmann