Yes, you can only obtain a “International Trade Certificate (ITC) Export Only” (if your product meets the definition of a natural health product as per the Natural Health Product Regulations). These certificates are only for products that would fall under the definition of a natural health product in Canada, but are not sold in Canada (and therefore do not have an NPN). They come with a cover letter stating that the product has been manufactured for the purposes of export only. FHCP would require a valid site license and/or drug establishment license number in order to issue such a certificate.
Please note: Unfortunately, Certificates of Free Sale or regular International Trade Certificates are not available without an NPN/DIN.