The Sage cloud version you are looking for is actually the same version you have.  There isn't a separate cloud-based solution but the subscription license of Sage 50 has some cloud features.  If you are looking for a cloud option I would look at hosting your existing Sage on a cloud server.  We have helped many client's setup and migrate their Sage to a cloud server.  You can reach out if interested in more info.  [email protected]