Each plan shall be conducted by or through (i) a nonstock or stock corporation organized pursuant to the laws of this Commonwealth; (ii) a foreign corporation that is subject to regulation and licensing under the laws of its domiciliary jurisdiction that are substantially similar to those provided by this chapter; or (iii) a foreign corporation that is licensed as an insurer in its state of domicile and authorized to operate, conduct, or administer a legal services plan under the laws of any state. Any foreign insurer licensed pursuant to this chapter shall not be authorized to write any other classes of insurance under this title.