I suppose this model is around 50 years old. I've done research, and it doesn't seem to be listed anywhere on the internet.
However, where I live, it's relatively common and is usually seen in older areas of town. They are always mounted on wooden
poles. They are always either mercury vapor lamps,or HPS lamps. Help identifying the model or the year in which it was
produced would be greatly appreciated!

These are called NEMA fixtures, which use clip-on optics. That one has an acrylic bucket refractor optic, but these were also sometimes used with gumball glass refractors or even a radial wave reflector.

It's a little hard to tell from the photo, but it was most likely made by American Electric Lighting or Cooper (earlier versions of the Cooper were made by Westinghouse). Both the American Electric Lighting (11 series) and Cooper (RMA series) versions are still made. GE also made a similar version in the 1960s and 70s (model 101SA).

That fixture most likely dates from the 80s or later if it's HPS.
Mercury vapor NEMA heads like these were made from the 60s up until 2007.

Earlier NEMA heads were made as early as the 1950s possibly 40s but usually had a more rounded shape to them.

These are called NEMA fixtures, which use clip-on optics. That one has an acrylic bucket refractor optic, but these were also sometimes used with gumball glass refractors or even a radial wave reflector.

It's a little hard to tell from the photo, but it was most likely made by American Electric Lighting or Cooper (earlier versions of the Cooper were made by Westinghouse). Both the American Electric Lighting (L series) and Cooper (RMA series) versions are still made. GE also made a similar version in the 1960s and 70s (model 101SA).

That fixture most likely dates from the 80s or later if it's HPS.
Mercury vapor NEMA heads like these were made from the 60s up until 2007.

Earlier NEMA heads were made as early as the 1950s possibly 40s but usually had a more rounded shape to them.

Line Materials also made a NEMA head with glass bucket optics.

Thanks!