Best place to buy replacement parts for a laptop?

I've got a Dell G3 3579 that's in a dire need of a battery and a bottom panel replacement. I've thought of buying them off aliexpress, but I'm a bit skeptical of it... So ig my question is whether it's OK to buy stuff like replacement laptop batteries off aliexpress.

E: I've checked, amazon does not ship to my country... I'm also technically asking if anyone knows any trusted good replacement battery manufacturers that I should look for...