Any political subdivision may provide for the inclusion of buses, vans, or other motor vehicles used by senior citizens groups to transport members in a motor vehicle insurance policy of the political subdivision. The political subdivision may require payment by a senior     citizens group for any increase in the premium rate charged to the political subdivision which is attributable to the coverage provided to that senior citizens group. The political subdivision may provide for a payment procedure to require the payment of any premium or premium portion attributable to the coverage provided for the senior citizens group.