If you are looking download CVS packages, have a look at
https://openacs.org/4/checkout.
There is currently no page which can be used to retrieve a particular repository package (and here I'm referring to the repository that is accessed by the APM when you click on on any of the links on your server's Install Software page). However, each released version of every package is available in .apm format (just a compressed tarball and can be expanded with the standard 'tar zxvf...' command).
So, the answer to your question is...yes, but some effort is involved. Here's how:
o go to https://openacs.org/repository
o select the version (branch) you want
(you'll see a description of each package)
o add "manifest.xml" to the end of the displayed URL
(you'll get the manifiest.xml file in your browser)
o copy the required download-url from manifest
o paste this URL into your browser address field
(e.g. https://openacs.org/repository/5-1/some_package_version.apm)
o save the file with your browser
o expand the .apm file in your server's "package" directory
o go to http://your_server/acs-admin/install
o select Install from local... and the package should be listed
(not sure, you may have to restart your server before install)
That's it.