I looked up NY State, Pennsylvania, and Virginia, Pennsylvania had what looked like a graded list, and didn’t say exactly what the graded solos were for.
Virginia and NY State required membership in the specific organization in order to access the info. I guess you’d have to do a state by state search. Maybe if other people read your request, they’ll post the audition materials from their states.
Wouldn’t it be best to make it a suggested list so as not to be restrictive?
It seems to me that you are setting the bar pretty low. I would at least have one orchestra part, like the Waltz of the Flowers after the cadenza, and some rhythmic pieces like Le Bon Petit Roi d’Yvetot and the Pavane from Solos for the Harp Player. But that’s just me.