I'd put this in the 'life's too short' category, and buy precut treated
stringers from the deck aisle at the Borg. At most, they will need a
little trimming to match the as-found conditions, and to make sure the
rise and tread depth are the same for all the steps.

Since most codes allow a riser height from 7" to 8" overall, what
makes you think the pre-cut stringers are going to be at the 7" riser
height that the OP requires? If they are, say, 7 1/2", they won't
work, no matter how much "trimming" you do. With a little careful
planning, cutting a set of stringers is a pretty easy project.

JK