Best Budget Hard-Plastic Mice and Keyboards for Shared Computers?

I'm in charge of managing the computers in my university's microscope facility. Since only trained users have access, the devices aren't abused. However, due to heavy usage, I need equipment that's easy to clean. Soft or rubber parts get grimy, and anything complex is a pain to maintain. Currently, we're using OEM HP and Dell keyboards and mice, but they're pretty terrible.

I have a couple of issues: the 'easy to clean' options tend to be overpriced and not user-friendly, and the 'professional' ones often have the same OEM issues or soft surfaces that don't hold up. I recently tried a Logitech G203, which is decent aside from the annoying RGB lights, but I'm still looking for alternatives, ideally a mouse and keyboard combo that stays under $60. Hard plastic is a must, and low profile keyboards are preferred since they're easier to clean in our dust-free environment.

I'm open to hearing your recommendations!

Edit: I appreciate all the feedback! The suggestion to buy cheap and replace often is looking like a solid choice. I'm planning to order a Cherry DC 2000 set with a mouse and the Lenovo Essential Wired Keyboard and Mouse Combo to see what works best for us.