I learn something new almost every day on this forum Bruce. I recall my 71' had two keys and when I got the 77' it came with two keys. So everything was normal right? They are a left cut and right cut keys, but alas, not original. It is a 1/77. Maybe I got the last of the 2 key cars and Datsun was trying to get rid of old inventory .
As far as door locks go, RCB gave me a good pointer. I could not unlock the doors with a key, but I could lock them with a key. They were just worn out on one side. RCB's suggestion was to just reverse the door locks. Now I can unlock with a key. To lock, like mentioned before, just hold the handle up. Saved me having to replace locks and ignition just to have a matching key.