(a) Any organization organized under the laws of any State and subject to inspection and regulation under the banking or similar laws of such State shall be eligible to become a member under this chapter if—

(1) it is organized solely for the purpose of supplying credit to its members;

(2) its membership (A) is confined exclusively to building and loan associations, savings and loan associations, cooperative banks, and homestead associations; or (B) is confined exclusively to savings banks; and

(3) of the institutions to which its membership is confined which are organized within the State, its membership includes a majority of such institutions.

(b) In all respects, but subject to such additional rules and regulations as the Director may provide, any such organization shall be a member for the purposes of this chapter.