You know I have a slew of Agave Parryi truncata babies and I've seen them hardy down to like 5b. I also have variegated Agave Lophantha (center stripe Agave), they may or may not make it in 7b, they say 8a on most sites. However they are a "small" Agave and could be potted or maybe just planted under a tree to keep it a little warmer in winter, I have a small one and it would be worth a try as they are so cool. I'd love some cuttings, it's always worth a try. I have several plants in my garden from cuttings.
