Is there a way for Vagrant to import a local box file with a specified version?

Based on this answer, to specify a version for local boxes, you need to create a metadata.json.

The minimum content of the file looks like this:

{
    "name": "USERNAME/BOXNAME",
    "versions": [{
        "version": "X.Y.Z",
        "providers": [{
            "url": "package.box"
        }]
    }]
}

Where the package.box is the relative path from metadata.json

After that, you can simply run vagrant box add metadata.json to add a new box with a version.

Warning:

Vagrant stores the metadata.json url in the ~/.vagrant.d/boxes/FULLBOXNAME/metadata_url file. So, bee careful with names, you could't use the same name from different sources.

after import your box file

cd ~/.vagrant.d/boxes/<username>-VAGANTSLASH-<boxname>/
mv 0 <specified version>