I will have to check out the whirlpool water heaters next time I am at a Lowes store. Then I can say that I have seen one.
There water heaters must be a different line then there appliances. I have alway's been happy with there appliances. I have been doing factory authorized service for Whirlpool for 20+ years now. They make some nice stuff.
I am sure you have looked around, but maybe you could post the part number of that thermo coupler and I could do some research on it. Maybe find another source for you to get them from.
Would be great to if could snap a photo of it or a old one you have around. Then use the "Additional Options" to download the image into your next post.
I would be interested to see what they look like. You would think that someone other then Lowes would have these.