What’s the best, reasonably priced, handheld device I can buy to play GameCube games?

Please tell us your upper limit for your budget because our definitions of reasonable might differ.

How portable do you want? I have an RG Cube I just beat Wind Waker on. The screen is a little small but it's pocketable and the battery lasts quite a while.

Well, define "Reasonably Priced". I dig the Steam Deck for that kind of thing.