It will be fine for stock. How far you can overclock with that cooler depends on a number of things, as with any overclocking setup. How well does the cpu overclock at a given core voltage? If it requires more vcore to remain stable than another 7700k then it will generate more heat and require more cooling.
What are the room ambient temps like? If your pc room is typically around 30c or higher it will require better cooling than a pc in a room that's at 20-22c.
How is case ventilation, do you have a mostly closed off case with a single fan exhausting at the rear or do you have a well ventilated case with a couple intake and a couple exhaust fans keeping the case air temp (that's cooling the cpu) closer to ambient temp.
Those...