I like Littman
A student needs to be able to hear basic sounds of the heart, lungs and bowels. There is no need to spend a lot of money at first and the student should look at a basic model by Littmann, my personal favorite.
Purchase the Littman cardio. It's around 275.00 bucks, excellent, and has a long life. I have had it for over 20 years works new each time. Also, with all the latest updates, including sonography attachments. This is a great time for purchases
The one I have is the Littmann Classic II S. E. It has “high acoustic sensitivity, patented dual frequency range diaphragm, combination chest piece with non-chill rim, compact and durable design, patented Littmann soft-sealing ear tips, three-year warranty, made in USA”. Unless of course you’re boycotting the 3M company, if they still make it!