Most of us rarely play anything earlier than Mozart, except for the occasional arrangement. And it's a common misconception that the clarinet doesn't have any baroque repertoire. We do have a few baroque works, though, including pieces by masters Vivaldi and Telemann.
In this article, Eric Hoeprich argues for the use of historical instruments (and not modern clarinets) in Vivaldi's concertos. You can definitely hear the historical clarinets in the YouTube recording above, but I can't say they whether they conform to Hoeprich's specific criteria.
However, I think this performance (below) of Telemann's Concerto is great. The combination of old and new - modern clarinets alongside harpsichord - is fascinating.