We do not have a download file for the latest version (5.21.700.7523), but you can try downloading it from the developer's site
Download version 4.270.1 from Mac Informer
Version: 4.270.1
Date update: Apr 12, 2022
File name: bluestacksinstaller_4.270.1.2803_2d767490223ea924053a33393c85eb83.dmg
Size: 682 MB