I believe that Tippers are now the only people making these period style plates and they can make them to fit exactly the fizzy rear number plate size (9.5" x 6.5")
http://www.tippersvintageplates.co.uk/p ... ent&part=6
They are not cheap at around £38 and I have not been able to negotiate a discount for us yet but if you mention that the Club sent you I will keep working on them.
Cheers
Per