(a) The health-care insurance coverage shall be provided through a carrier incorporated under the laws of this State or legally authorized to transact business within this State, having adequate servicing facilities to carry out the terms of the contract.
(b) The health-care insurance coverage shall be provided by a carrier offering, at the employee's or pensioner's own expense, optional supplemental or extended benefits coverage to each regular employee or eligible pensioner and similar hospital, surgical/medical and supplemental or extended coverage for such employee's or pensioner's spouse and dependents.