Just thought I'd give a little update. Second quote finally came back. $795 for the install. They want to use a 30A circuit, too. Rather than the last guy that wanted to use 20A. I think there was a little confusion and I gave them the docs from SPX again because I think they really want to use 20A. But that'll probably even be a little cheaper then.
I had a feeling that $1300 was a little absurd. This is still probably marked up substancially. But not enough to make a fuss about. Apparently the association uses them a lot and they have experience with EVs so I'm not too worried about material quality. As long as the voltage tests out after the install, it's all good.