So, it needn't be very small or battery, but is for a camper.

So lasers are out 'cos the camper will scramble the toner enroute. So, any smallish inkjet that's rectangular (no fancy shapes) and has no protuberances that can't be folded away (so it can be efficiently stored) would do.

How about the HP H470Wbt? Or bigger but cheaper the Epson xp-200?