A Surface might be an alright option. Last time I checked, the i5 and below models were fanless. With a good case it should be relatively rugged. Linux on Surfaces is fairly decent; I put Zorin on a Surface Go 2, and everything seems to work apart from the IR for face recognition. Battery life has been much better than in Windows, which is a plus.
https://github.com/stivvin/carcinizationpatch