Hi there
I have just reclaimed the original registration on a BSA A65. To claim the original number you have to have evidence that ties that number to the bike, having the number plate on it's own does not count, the DVLA will accept the original log book, old MOT's, old Tax discs or if you can get it from the authority that first registered it a copy of the original registration paper but you will find that most authorities destroyed them when everything was transferred to Swansea. You also have to have a dating certificate from an owners club. Failing the above you can apply for an age related plate but you will still need a dating certificate from the owners club and that is where your problem starts, because everything hinges on the frame number. I do not have any experience with Raleighs but am sure that there will be an owners club and if you contact them they may be able to advise you on the best course of action.