How can I setup a Manage Magazine Subscriptions in CiviMember
we (Fuzion) worked with John Derry when getting The Monthly going as a Sub on CiviCRM. There was a lot of nuances they needed particularly involving ensuring that Gift Sub reminders went to the original Giftor etc, etc. I think that since that time they have had internal resources to further finesse their subs process in ways that I cannot explain, but potentially someone at The Monthly could.

But in essence yes you can treat a Subscription as a Membership. 

If you detail out really clearly what the exact specs are you need then folk may be able to volunarily help you assess how to achieve this in CiviCRM or you can reach out to one of the Partners for professional advise and support (and customisations/extensions if required).

NOTE: The OP referred to Joomla, for readers who are using Drupal CMS, there are also significant workarounds that can be achieved with either Drupal Webforms or with CiviCRM Entity in terms of finessing the subscription process for the user.

Hope that helps