Hi JimDon,
Good Luck. I have another one of these in my watches with a blue dial. It was listed as an Ambassador when I bought it, but in the last year I have not been able to confirm this. Both of my watches are unusual in that they are stamped N2 on the backs, but the Buren 1322 movements are M8. The markings in the case back lead me to think that these are Swiss manufacture. The 1321 1322 movements were used in a variety of different Swiss watches. The 1322 is for a domed dial, and the 1321 is for a flat dial.
I don't think these are super rare, as lately I have seen two with the blue dial and one with the green.
Let me know how your search goes. My blue dial copy runs, but quite fast. I might me tempted to trade for something interesting, if you are willing to get it to be serviced. These Burens are iconic movements, but require expert service.