(a) Every credit union shall be required to obtain deposit insurance satisfactory to the department before it may conduct business and accept deposits, except that credit unions which have had their deposit insurance coverage withdrawn or canceled may, in the discretion of the department, continue to accept deposits, provided that, within six months after withdrawal or cancellation of insurance, such credit unions shall obtain deposit insurance written by an insurance company authorized to transact business in this state and acceptable to the department or by the National Credit Union Administration. The department may, in its discretion, for cause shown, extend the time limitation in which deposit insurance must be obtained.

(b) Deposit insurance required to be obtained in subsection (a) of this Code section need not be in excess of amounts insured by the National Credit Union Administration at the time the insurance is obtained; but, whenever the insurance coverage is, in the opinion of the department, less than amounts insured by the National Credit Union Administration, the credit union shall be required to post a sign in boldface print, in letters at least four inches high, at a conspicuous place near the entrance of such credit union, which states "Deposits Not Insured" or "Deposits Insured Up To (insert amount of deposit insurance)." Such wording shall also follow the name of the credit union wherever it is written or printed and shall be posted in writing which is easily legible in letters at least one inch high at each window or desk receiving deposits.