Glad someone called me out on being too picky! :)
I'm not sure that this falls into the "affordable" category, but the Roland R-09 will record up to 24-bit/48kHz WAV and 320kbps MP3 files and costs around $400. I have one, and it actually records quite nicely just on it's own, especially with it's built-in low cut filter on.
If a microphone was needed, the Electrovoice RE-50 is an old standby for a good, omnidirectional, dynamic microphone. It's $150 on Amazon, a good price for that mic.
I understand the position that BPL is in--starting a new feature, working out equipment issues while keeping money in mind, paying for additional bandwidth--as well as those who don't find the audio quality to be a problem. The quality has certainly been good enough to understand what's being said, and if that's the only objective, then everything's just fine. However, it would seem clear that hearing what's said really isn't the only objective; a transcript of an interview would do that just as well. No, it's not a Morton Feldman string quintet, a La Monte Young drone piece, or a Wagnerian opera, but it is human voices and their surroundings, which have just as much sonic depth in their own right.
I look forward to seeing BPL offer more options to suit varying tastes, love the podcasts (espcially this one!), and very much appreciate the fact that my opinions are heard and considered.