YES… the original exhaused were made by Sankei. Their model code is 2048. There is also the Honda reference is HMMA3 (I presume that stands for Honda Motorcycle then MA3 being the 1100R part number code). The German model exhausts that have the restrictor in place have “G” on the end (HMMA3 G)
These are stamped on the the exhaust muffler near the mounting bracket that bolts behind the footpeg mount. YOu need to get down on your knees and look underneath.