7-string Not Even Slinky

[Wierdoom]

Hi,
I just got a 7-stringer, and I would like to use the Not Even Slinky strings for it. I am aware that there is no 7-string pack for it, which is why I came here. To use it for a 7-stringer, I'm going to add an extra 'wound' string for the b. However, I do not know what guage to use for the extra string. I was thinking maybe a .64/.66, so it would be 012-016-024-032-044-056-66. Would this work well? I play mostly metal (much of it detuned), such as SOAD, Skinless, Korn, Death, Slayer... etc.
Cheers!

-Wierdoom

EDIT: I have a Schecter Damien 7.