Any standard compound microscope should work well with the Celestron Digital Microscope Imagers (CS-DMI, and CS-5MP)
We tend to recommend compound microscopes from traditional vendors such as Zeiss, Nikon, and Olympus as these microscopes should all have the industry standard ocular diameter of 23 mm.
Please verify that the ocular diameter is 23 mm (the industry standard) before purchasing your new microscope from any vendor.
Ocular diameters that are greater than 23 mm should not be a problem as long as the diameter does not exceed 30 mm and the adapter ring that comes with the imager is used.
Unless you are teaching a microbiology course, students are not going to be using a 100x oil immersion lens. See if a supplier has a model without the 100x oil immersion lens, to make it even more affordable.
Flinn Scientific and Wards Science and many other vendors carry compound microscopes designed for education. Celestron also carries an affordable entry level compound microscopes. A link to one we have tested is located below.
Celestron Labs CB1000CF Compound Microscope
If you are interested in microscopes and digital imagers you may find our recorded webinar on this topic useful. A link is located below.
https://www.vernier.com/video/ask-me-anything-digital-imagers-and-digital-microscopes/