A member bank may not engage in a transaction described in §223.52 unless the transaction is:

(a) On terms and under circumstances, including credit standards, that are substantially the same, or at least as favorable to the member bank, as those prevailing at the time for comparable transactions with or involving nonaffiliates; or

(b) In the absence of comparable transactions, on terms and under circumstances, including credit standards, that in good faith would be offered to, or would apply to, nonaffiliates.