[rrpjr]

Neither the Porsche Option Decoder nor Peter Morgan's Original Porsche book lists a "C26." (A plain "26" is noted for this year model, and it is "Activated Charcoal Cannister.") Morgan breaks down 1987 models in terms of destination as such: Japan, US/Canada and RoW (rest of world), determined by chassis number or VIN. If you were to provide the car's VIN (long number beginning with W), might be able to figure out its destination. But Morgan's book doesn't list a "destination country code," and that is my only source. Perhaps some will pipe up with other sources.