Preliminary note:
You are in need of debugging on a specific device after release, but I will also address testing before release.
One resource to consider is vendor loaner or rental programs for development partners (developer partner programs). Some provide short-term access for testing purposes affordably, perhaps even free.
Most of the hardware vendors have developer programs, which offer hardware for reduced costs or even free (e.g. Samsung, Motorola, Apple, BlackBerry (for BlackBerry Alliance Members), LG). Check them out for the devices you want/need.
There are publicly accessible 'physical' test labs that you can just walk into (or reserve time). They are usually called open device labs: starting point, Google search. Check out if there are any in your neighbourhood and what devices they have.
There's the occasional 'crowdsourced' testing community like uTest that you can ask around.
Note that there are also many on-line services for testing your apps on many devices like AppThwack, TestFlight, TestObject, TestFairy, Keynote a.k.a. DeviceAnywhere, or Xamarin test cloud that maybe have the device you want to test on.
You would also use these before releasing your app, and although these are not 'definitive' testing platforms (there's much to be said for testing on real devices), any tests helps.
Note: Useful overview article