There's a *very* fair chance you'll be able to cast higher level spells - just not from memory.
Typically, in cRPGs you are either outnumbered or outclassed. So, you'll likely end up fighting higher level mages than your own. They can very well be in the possession of spell scrolls that are too high for you to scribe. You can still *read* the scroll though; as a one-time-use item.
There's probably a scroll of TimeStop somewhere, or Wish.
Possible but I don't see how the wish spell would work...even in 5e the functionality of the spell in terms of the spell is limited with the caveat that it could do just about anything the DM is willing to allow. If something like that is in the game it will probably be a quest item rather than a scroll and then you'll be offered specific uses during story events. But I doubt anything like Wish will be made available to players.