When any company subject to this chapter agrees to reinsure for another state or county mutual fire insurance company the whole or any part of the risk, as authorized by §56-21-124, it shall issue its regular policy of insurance for the amount of the risk, or part thereof so reinsured upon application therefor, and the company whose risk, in part or in whole, is reinsured, shall be liable to assessments or to pay a premium at the same rate as other members of the company for like insurance.