Suggest you have a VIN plate made with the details from the V5c and attach it on the off side of the car somewhere suitable.
I believe they are available on the usual online auction site but if you are stuck a firm local to me makes good quality signs of this sort, at a very reasonable cost, less than half what the Marlin Owners Club ask and to your design if you wish.
The VIN plate in the middle of this page was made to the design provided by the customer, I have seen a copy and it's really nice quality. I understand he submitted a JPEG file to them.
http://www.wljones-engravers.co.uk/metals/
I will be having them make a new VIN plate for my Berlinetta when I am ready. (I have no connection with the firm)