I've found three fast lenses made by Kowa on the commissioned sale in Tokyo. They appear to be X-Ray lenses: 55mm/f1.1 (24,000 JPY), 65mm/f0.75 (80,000 JPY) and 95 or 90mm/f0.95 (80,000 JPY). They all look like Rodenstock Heligons. None of them are listed in Klaus' Macro Lens Database.