Hi Martin ...... perhaps you can educate me. I note that you are in Gibraltar .... is your friend there as well? If so why the requirement for the car to be over 30 years old? Are the 'rules' in Gibraltar different to the UK. Maybe it's something to do with the situation with Spain.
As you may be aware quite a number of KVA's were built and not submitted for an SVA test (prior to the change to IVA) and not correctly registered. I know of several that have a V5C document that shows the car as a Cortina !!!
I've recently advised a couple of people who are rebuilding old KVA's where this is the case and told them that problems will arise when they insure the car. Also if the police see the car and check the registration, and it comes up as a Cortina, then there will be a load of grief. Which could involve the car being impounded.
Good luck with your search but be very diligent.
Best regards
Steve.