I would suggest not using your local key-cutter - as they will probably replicate existing key - with 40 years wear....
I found a man in Scotland/Ebay who cut keys to Volkswagen number - the keys he supplied worked much better than the original (worn) key.
Point being - get the keys cut from the VW number - not copied from old keys if possible.
I did get the petrol cap key "copied" by local cobbler/keycutter as there was not other option I could find - and that worked fine -
Hope that helps