An insurer may invest in the preferred or guaranteed stocks or shares of any solvent institution created or existing under the laws of the United States or of Canada, or of any state, province, district or territory thereof, if all of the prior obligations and prior preferred stocks, if any, of such institution at the date of acquisition by the insurer are eligible as investments under this chapter; and if qualified under subsection 1 or subsection 2 following: [1969, c. 132, §1 (NEW).]