I had one of the original Devon fitted Whale pumps with a combined big rubber button and electric pump below the spout. The rubber seal on the motor spindle had long gone so after filling up the cupboard with water once or twice I bought a pump off ebay that is intended for PC watercooling - with a brushless motor. This pump has a ceramic/plastic rotor and no water seals around rotating shafts , and it will run between 5 and 12 volts. I am quite happy with its speed at 12 volts when it is having to suck through the valves of the rubber button hand pump that it is still in 'series' with. I bought a service kit for a boat pump with a similar design and replaced the valves and springs in the rubber pump part. I cut up the old electric pump bit and turned that into a simple spigot that connects a hose to the rubber pump. Put the new electric pump in line below the spout in the sink - didnt want a submersible pump because it doesnt go through the hole in the top of the Devon removable tank we have. And it relies on having a smallish hole to stop water slopping out as you put the tank back in at an angle. So you still have to prime the pump by thumping the rubber button a few times, but once done it takes a while (weeks) for the water to drain back into the tank and the pump needing priming again.
