With Intel processors, overclocking is only reserved for the K models anyway (e.g. i9 9900k), and a mid-range CPU air cooler is generally sufficient for your CPU.

E.g. something like this:

be quiet! Pure Rock 2 (15.50cm)

However, if you want to upgrade and insist on an AiO (overclock, more cores, etc.) then I recommend an AiO with more radiator surface (if your case allows it), in the range of less than 100.- you can find something like this, for example:

Arctic Arctic Liquid Freezer II 240 (6.30cm)

The cooling performance of such a small radiator is hardly better (if not worse depending on the scenario) than that of a 30-50.- air cooler, so this AiO would make sense where there is no room for an air cooler.