The entry level MTB shoe from Shimano (some variation of the M020/021/022 depending on what year it is and where you are) may be your answer. My 020's had a piece of sole that had to be cut out with a knife before the cleats could be attached. This would be waterproof. They are lace up shoes that are reasonably comfortable to walk in while still having the stiff sole.

The next up shoe in the series (M038/39 etc) has a screw on cleat cover (looks like part of the sole) that is removed prior to attaching the cleats. While appearing to be intact, it may not be suitable for walking in water.