Damn, I guess this is the downside to living in a state that's #1 in diabetes and obesity. Not a whole lot of exercising going on. There is a gym that teaches cardio kick boxing. However, it's completely non-contact and low impact, which is maddeningly unhelpful.
As far as I know, there is no gym that does boxing here. Also, there is a martial arts club that teaches traditional jiu jitsu and Brazilian jiu jitsu. I know nothing about either of those, but if they can provide anywhere near the cardio that Muay Thai has given me, I'd be willing to give it a shot.