Personally, I have my doubts but I've never studied enough examples to be sure.
It looks a bit rough and ready. I've seen others with "Plaque G" and the "AW" stamp inside a box, which this one doesn't appear to have.
There are some more buckle pictures in this thread
https://omegaforums.net/threads/strap-and-buckle-sizes-for-tri-compax.45956/
The main reason for my doubt is that this seller seems to have a limitless supply of these buckles.
Click to expand...