Why don't they make relay cutouts?

[Sunny the Model A]

Before you go yapping on about alternators and diodes here me out. I have had nothing but endless grief with those alternatives. My s10 and 53 210 have gone through 5 alternators and I gave up on em. and my A had a bad reaction to diode cutouts. When I got my A it had the wires disconnected from the cutout, turns out it had a diode cutout. when I ran it with the generator charging on minimum, it only drove about 10 miles and burned out. Then I shelled out and got a nurex, same thing. this time it boiled the battery. I got an original cutout and it worked magically. They key is that it prevents the generator from putting out too much voltage, it turns off after 6.8v or so on my truck. I want to find a relay cutout supplier for when I'm rebuilding generator and eventually making new generators. I know diodes are common but in my opinion they suck. So is there anyone who makes the relay cutout or is there blueprints for the original? thanks in advance