A lot of the clinical information and study looks a lot like this one: https://www.acc.org/latest-in-cardiolog ... troke-risk
In a word, it points out that the available information on the risk of stroke, specifically -- and yep, only wit aura, not without -- is both conflicted and limited. So, we really can't say how big a risk it is.
But here's the thing: anyone prescribing you, or thinking about prescribing you, the pill should be informed if you have migraines (and then ask if they are with or without aura), and will take that into account, as well as other information that would concern any risks, in what they decide. If a physician has prescribed you oral contraceptives and you have given them all your health information, unless they aren't doing their jobs in the most basic way, they only will have prescribed you oral contraceptives that are safe for you or at the very least, where you will be safer from those risks than you would be with a pregnancy.
Does that make sense to you?