There's various different cases you can 3d print yourself. Just search them in any 3D printing search engine and you'll see various designs.

Is it inherently dusty where you are from? I've never had any piece of hardware fail on me because of dust. However, I do tend to keep on top of maintenance for the more important devices, and by that I mean a can of compressed air. I've definitely damaged a few fans, forgetting to hold them when cleaning them though .