I assume the diapers are the disposable variety.
If water is available for washing, maybe you might consider the old fashioned reuseable linen(?) varity. They would take up less room, almost certainly be cheaper and could have other uses. (a facecloth springs to mind....or maybe not... <img src="/images/graemlins/grin.gif" alt="" /> <img src="/images/graemlins/crazy.gif" alt="" />)