Tudor is/was a large photo-processing lab in UK, doing mail-in services and collections from retailers etc. They sent a new film back with the prints, or did so if you ticked a box on the envelope and paid the extra. There may also have been Tudor film sold in a pharmacy / small-retailer used as a collection point for the lab services. It is one of these rolls which you have found. If there is anything on the cassette concerning country of origin then Italy suggests Ferrania/3M, Germany might suggest Agfa, Japan might be Fuji or Konishiroku (if it is very old!), UK/US/Mexico might suggest Kodak. At various times, these companies all made basic films for retail as "own brand" films in differently printed cassettes.