And keep in mind, just because it's "in stock" doesn't mean that's what your options are limited to. Sometimes the answer we need, is no, whether we want it or not. And in this case, no, is the answer YOU need.
NO. You should NOT overclock using ANY cheap power supply, regardless of the system or hardware in use. Overclocking is an ENTHUSIAST endeavor, and enthusiasts, or experienced overclockers, know that overclocking on a cheap power supply is asking for trouble not only with the stability or viability of the overclock, but with the safety and potential lifespan of the hardware as well.
NO. You should NOT assume that one 550, 650, 750w unit is the same as any other unit with the same capacity, because that couldn't be further from the truth.
NO. You should NOT simply "settle" for some cheap power supply because it's all you can get your hands on quickly, or any other component for that matter. I realize that sometimes it FEELS like you have to have the hardware NOW, but the reality is, you don't. You don't HAVE to have it NOW. You CAN wait. And if waiting is what you need to do in order to get something that is higher quality but still within your budget, then THAT is what you DO.
You are not alone in this. You are not the only person in the world that is being affected by a limited supply of hardware because of Covid 19 basically shutting down China for four months, both shipping and manufacturing. You are not the only person facing shortages and high costs because of it. If you want to end up with garbage and a POS system that was simply a waste of your money from the start, then settle for cheap parts. Otherwise, do like the rest of us have had to do and make an allowance for the fact that you might have to wait longer than normal to get what you really want or need, and that you might have to pay a little more for it.
Or, you can just buy the cheapest piece of crap you can find for 40 bucks, overclock the heck out of your system and burn your house down. That's an option as well.
In your price range, the two units madmatt recommended are probably your best choices.
You should probably read BOTH of these guides.
Below you will find MY standard list of recommended power supplies and beyond that this thread is intended as a landing place for questions or discussions regarding specific units, platforms or related PSU tech, all of which are all welcome to be discussed here. If it's related to power supplies...
forums.tomshardware.com
https://www.tomshardware.com/reviews/low-cost-psu-pc-power-supply,2862.html