(ii) send the customer substitute merchandise of equivalent or superior quality, if the customer is extended the opportunity to return the substituted merchandise and the seller promises to refund to the customer the postage cost of returning such merchandise together with any portion of the purchase price previously paid by the customer. Prior to or at the time of shipment of the substitute merchandise, a notice shall be provided to the customer stating the right to obtain a refund and reimbursement for the postage cost incurred in returning the substituted merchandise. For purposes of subparagraphs (i) and (ii) of this paragraph, merchandise may not be considered of "equivalent or superior" quality if it is not substantially similar to the merchandise ordered, or not fit for the usual purposes for which such merchandise is used, or if the seller normally offers the substituted merchandise at a price lower than the price of the merchandise ordered.