It doesn’t look to me like anything is actually
broken or missing (though hard to tell since your photos are blurry), the sliders have just popped out, and a few keycaps came off. You should be able to just reassemble it.
Those switches look like they’re
uncovered Cherry M8 switches. That page has diagrams and pictures of the internal, disassembled.
At least you know what switch type to search for if you need replacements. I very much doubt you can buy individual switch parts, especially for switches as old as these.