At least the green one is cheaper on Amazon: $23.99. Just search for “cast iron teapot dragonfly”.
These cannot be heated on the stove. You have to heat the water elsewhere and pour in. That’s my current setup and it really isn’t a problem, but people attempting to use this on a stovetop could be surprised when it melds to their burners.
I bought the black one almost two years ago (for a good bit less) and have been very happy with it.
I fill it with hot water to heat it up, dump that water, put in the tea leaves, and put hot water in again.
As noted, it’s a tea pot, not a kettle. It’s for steeping tea, not heating water. I use an electric kettle for heating.