Yes, there might be. The Naruto fandom is quite large and diverse, so it's possible that some fanfiction writers have created stories where Naruto is seven feet tall. You can try searching on popular fanfiction websites like FanFiction.net or Archive of Our Own.
One possible plot could be that Naruto's sudden increase in height gives him an advantage in battles. Enemies might be intimidated by his new imposing stature. For example, in a fight against a powerful villain, his height could make his punches more powerful due to the longer reach.
The height of 13 stories can vary depending on the height of each floor. But on average, if each floor is about 10 feet, 13 stories would be around 130 feet.
85 feet works out to around 7.73 stories. Usually, the height of a story can vary, but for a rough estimate, if we take 10 feet per story, it would be close to 8.5 stories. But with a more common 12-foot story height, it'd be a bit less than 7 stories.
His 7 - foot height in fanfiction might enhance his combat abilities in several ways. Firstly, with his increased height, he could have a better view of the battlefield, spotting enemies and their movements more easily. Moreover, his long limbs could be used to execute powerful and wide - sweeping attacks, like long - range kicks or using his kunai with greater force due to the extended reach.