I've never seen it. I struggle to believe it's better than DIY with a container of sour cream + one of the Hidden Valley Ranch packets. That's the true ranch dip of the gods.
Interestingly, I learned how to make ranch dressing from scratch a few years ago. I always have the ingredients on hand, so I can make ranch dressing whenever I want.
The proportions are NOT super important. At least 1 teaspoon of each of the main dry ingredients but you can use more if you want.