Any insurance company organized under the laws of the state, whether by special charter or under the general law, shall be entitled to amend its charter or articles of incorporation, so as to acquire the authority to do any or all kinds of insurance business which corporations organized under the provisions of this chapter are authorized to do, and may otherwise amend its charter or articles, in any manner not inconsistent with this chapter, by a majority vote of all its stock, or, if a mutual company, by a majority vote of those members present and voting, at a meeting called for that purpose. Any such company may, with approval of the commissioner, increase or reduce its capital stock and, subject to the limitations hereinafter provided, may change the par value of the shares of its capital stock at a meeting called for the purpose, by vote of its stockholders as provided by N.H. Rev. Stat. § 293-A:10.01 through N.H. Rev. Stat. § 293-A:10.09. The par value of the shares of stock of any such company now outstanding or hereafter issued may be such an amount as the commissioner may approve.