No, sorry. A Mech for an OC has to be an OC Mech also. It doesn't matter if the Mech was mass-produced in Gundam, or Macross. Those series have no affiliation to the Universe/Dimension the world of Paranova takes place on. You could create your own type of mass produced mech or something to expand the canon of the universe, but it's going to have to bear the "United Paranoivan Military" on it, because all OC's are Mech pilots in the Paranovian Military, and all Mech's in the OC universe are for military use.