www.montanajacks.com
That is for a single solenoid, the complete controller (pn#38844) is NLA, so the option is to find a NOS on eBay (or the likes), or buy the solid state controller (pn#83668) for $380 (which is what I did).If I'm looking at the right thing, it's like a 30 dollar part available even at Tractor Supply

