Do they exist in the real world? No.
They were miniatures.
You're probably thinking of something toy-sized, but also no.
This is how tall they were. A little over twice the height of an adult man. Large enough so that close attention can be given to creating the little cracks and colors that show something long weathered.
When I saw the movie more recently, I wondered what the in-universe explanation is of how these were made. As in, they clearly tower over the surrounding rock so it's not as if they were carved right out of the large rocks.
I looked it up, and the guy pointed out some details I didn't notice.
A quarry to the bottom left where some stone was cut out.(1)
If you look closer, you'll notice the block lines on the statues only exist on the upper part.(2)
Granite block lines. You see?
The bottom part of the statues were completely carved out the rock, but for the upper one, stone was cut out of the quarry, brought up, and carved to make ‘em.
The miniatures were made out of rigid foam. With great lighting work, and some stuff done on the computer, you have the finished product.
I think people thinking the statues were real, or that they looked very realistic, is a high compliment to the people who made all this.