Watermark makes the sensor and sells it with a 5 foot lead, instead of the big one Davis does. I think someone on this site came up with a replacement, but I don't recall who.
A while back I was trying to find someone selling them cheaper and found on ebay someone had 10 of them and was selling them for $5 each so I bought them. But that was a while back and they are all used.
But I am confident someone here came up with a sensor that worked