I’m more likely to think it’s in the range of 500 years old. Probably a left-over from some Spanish expedition into the region.
The Spanish weren’t in the area 500 years ago.
Maybe 1750s earliest.
Stone grave markers from the 1800s show far more wear than this pillar. And the carving is remarkably crisp. This thing isn’t old.
That’s what it looks like to me, maybe for early converts from Spanish mission work who were not yet literate.