The Royal Pigeon Racing Association got back in touch and apparently I'd been unable to see a letter before the number so they are 'unable to trace the owner'. Hopefully there is no sick or dead racing pigeon around the Sale WP area. I do know the pigeon fanciers get up to some cruel tricks like separating paired birds and shipping one off for release in Barcelona...
The owner's contact details are sometimes stamped on to the underwing, or at least that used to be the case. I picked up a couple of racing pigeons at Orrell Water Park during my time as a ranger there and reunited them with their owners. On the second occasion the bird was dead when the owner turned up, despite it being alive a short while earlier when he rang me! I felt a right pillock handing him a dead pigeon. I think he believed me that it had been alive not long ago...
Yesterday I found a downed racing pigeon at Chorlton Ees while failing to find any more star migrants on a walk from Chorlton WP. I took its ring details through my scope. It was a Royal Pigeon Racing Association bird which have leg rings beginning GB. I discovered the best site for reporting lost pigeons is here
http://www.nehu.co.uk/lost.html
The North of England Homing Union gives the ring suffixes for all the main societies and the phone and e-mail contact details