To my knowledge, the only way to do this with microscopy is using fluorescent in-situ hybridization. You need a confocal microscope, which most university biology departments would have. Otherwise, you can also measure telomere length through Southern blot or flow cytometry. Any tissue type should be fine, as quality will rely primarily on extraction technique, and there are kits available for extraction of DNA from human tissue. However, there isn't really a good way to do what you want without access to a molecular laboratory that is authorized to work with human tissue.
