I've had the same failure on two Wisper King Surflo 2 gpm model 2093 water pumps. The spade electrical connection on the bottom of the pump corrodes and breaks off. This makes an otherwise operational pump useless. However, after replacing the pump for the second time, I decided to have a closer look at the old pump.
When I disassembled the bottom of the pump where the wires enter the pressure switch unit, I found that the switch is actually a standard microswitch which is pressed into the plastic switch unit body. It is fairly easy to pry it out and the replacement microswitch is available on the internet for $2.60 plus tax and shipping.
That's a lot better than the $135 for a whole new pump! It's a fairly simple job to remove four screws, carefully disassemble the unit, clean things up, pry ourt the microswitch and press a new one back in place, reassemble the unit and have a functioning pump again!
The microswitch is a Omron model # V-15-2C26-K sold by Did-Key Corporation as their part # SW-1432-ND. It is also a good idea to pack the recess around the wires with silicon after the pump is reassembled and wired up to reduce both corrosion and vibration.