I was a DJ and program manager for my university's radio station, and based on my experience I think there's a much larger opportunity here. Firstly, to answer your question, yes I think non-profit radio stations in particular would be quite interested in something like this, as they can't usually afford more than a 1 or 2-line phone system.

Now, the larger opportunity. If you could make it a less-specialized system and aim it at radio stations, I think you'd really have something. The biggest problem we had with taking calls on the air wasn't so much that we couldn't afford the phone lines, but that we couldn't afford the call-screener. If you had a system that could simulate let's say 10 lines, whereby people call in, it plays an automated screening message asking them their name and purpose of their call, and then it transcribed that onto the DJ's computer screen and allowed them to pick which calls to answer while the rest remain on hold, that would be awesome!

I don't doubt this could probably be done with some combination of Google Voice and Grasshopper. Then again, they don't market their products to this niche the way you could. The biggest hurdle with B2B is acquiring the customers, which often takes a focused message. But I digress.