(a) Subject to this section, an insurer may invest the insurer's funds in excess of minimum capital and surplus in a bond or other interest-bearing evidence of indebtedness of a:
(1) county or subdivision of a county;
(2) municipality;
(3) road district;
(4) turnpike district or authority;
(5) water district;
(6) school district;
(7) sanitary or navigation district; or
(8) municipally owned revenue water system, sewer system, or electric utility company with respect to which the municipality has appropriated, pledged, or otherwise provided for special revenues to meet the principal and interest payments of the bond or other evidence of indebtedness.
(b) A bond or other evidence of indebtedness of a navigation district is an authorized investment under this section only if:
(1) the navigation district is located wholly or partly in a county that has a population of at least 100,000; and
(2) the interest due on the bond or other evidence of indebtedness has never been in default.