(1) Such revenue bonds shall be sold in such manner as the board of directors shall deem for the best interests of the irrigation district, either at public or at private sale and at any price and at any rate or rates of interest, but if the board of directors shall dispose of said bonds in exchange for construction of improvements or for materials, such bonds shall not be disposed of for less than par for value received by the district.
(2) Notwithstanding subsection (1) of this section, such bonds may be sold in accordance with chapter 39.46 RCW.