I’m happy to be corrected but I’m pretty certain with out knowing either the vin or registration number you can’t get a V5.
If you have either a vin OR the reg number and ring DVLA and are lucky enough to get to speak to the 1 single helpful person that works there you MAY be able to get the other then fill in a form v62 (lost V5 form).
I recently had to break a good running scooter in great condition for parts for this exact reason which was incredible annoying.