You can get an air pump with tubing and air stone even cheaper than below. Keep in mind, a lot of people are doing this with no air pump at all (Kratky method).
That's big enough for a small container. Here's another though that's 100 GPH for only $12.99- https://www.amazon.com/AQUANEAT-Aquarium-Adjustable-Outlets-Hydroponics/dp/B0899NTXBF/ref=sr_1_7?crid=HF2HVFOQD2OY&keywords=cheap+air+pump+with+stone&qid=1672663217&sprefix=cheap+air+pump+with+stone%2Caps%2C128&sr=8-7
HTH. It's all pretty simple and straightforward.