Actually, clarinet and organ are a good match sonically. They have similar acoustics, and therefore, similar tones.
A few years ago, a local church organist asked if I'd like to do a piece for clarinet and organ. I had never heard of Rayner Brown. But the music was reasonably well written for the clarinet so I gave it a shot.
I think you'll agree it's a pretty cool piece, not too way out but not boring either.
Rayner Brown, Sonata for Clarinet and Organ, 1965