In short, use "backend-path" to include a subdirectory which contains your local copies of setuptools, wheel, etc. Create a file with the build hooks appropriate for "backend-path". Have that those hooks import the actual hooks in setuptools. Finally, set your "requires" to [].

Doing this means taking on a support burden of maintaining setuptools, wheels, etc. yourself. You'll also need to include their copyright statements in any distribution, even though the installed code doesn't use them.

(As I recall, that "etc" is hiding some effort to track down and install the full list of packages dragged in, but right now I don't have ready access to that code base.)