Notwithstanding any other provision of this section, a municipality, county, special purpose district, or public service district of this State which provides firefighting service and which administers a separate pension plan for its employees performing this service may invest and reinvest the funds in this pension plan in equity securities traded on a national securities exchange as provided in the Securities Exchange Act of 1934 of a successor act, or in equity securities quoted through the National Association of Securities Dealers Automatic Quotations System or similar service.