Clarinets are not known for social distancing, good thing you stopped it from running amok.
Was there any sheet music or books inside? It might help to identify it’s owner or school. I can connect you with appropriate music teachers in the area, and my kids are clarinet players, so they have connections too.
Kaat, if no one claims it, would you be interested in donating it to the West Seattle Community Orchestras? We have a lending library for students who can’t afford their own instruments. Let me know if so and I’ll put you in touch with our orchestra manager.