Be careful about stethoscopes. Some are not allowed for standardized clinical skills testing (mostly electronic stethoscopes, but I don't know if there are other limitations) and some may send an unintended social message. I've been told by a few docs that if a student has a more advanced stethoscope, like master cardio, he will be made fun of. You would definitely want to avoid getting a sub-par stethoscope. Point is, a stethoscope is a very nice, very thoughtful gift, but there are a lot of potential pitfalls to watch out for. If you want to get him a stethoscope, this is what most med students use:
http://www.medisave.net/littmann-cardiology-iii-stethoscope-black-3128.html
I know a vet student that said people who got wilder colors on their stethoscope got made fun of, but I've never heard that in human medicine.