If the spatial resolution is something not important to you, perhaps you can try to use a medical X-ray CT scanner. It will be necessary to calibrate the system to analyze your samples.
Another possibility according to Dr. Berg is the use of X-ray from a Synchrotron beamline. However, it will be possible you work with small samples. It is possible to obtain a very good spatial resolution, however, the results can not be representatives.
I have revised several papers in the last year regarding the use of X and gamma-rays to characterize materiais written by Indian researchers. However, I had never revised papers dealing with X-ray CT, only with gamma-ray CT. Try to do some contact with researchers from Punjab Technical University.
If you are still looking for an answer, I can support you. We have a micro-CT lab in General Electric, Pune, India. This system can provide upto 1 micron resolution.