Do narrow-band single-chip bandpass filters for audio frequencies exist?
You can build a pretty good narrow bandpass filter from a typical quad op-amp package and some resistors and capacitors.  If you want to use fewer components than that, you could look at one of the specialised filter ICs on the market, such as TI's UAF42. Opamps will probably work out cheaper though.
The requirement for binary output might be harder.  You'll probably need to add an envelope detector and a comparator.