Plaque with Buddhist Triad

The image shows a stone plaque with a Buddhist triad. The plaque is rectangular with a rounded top and a small chip missing from the top center. The central figure sits cross-legged on a lotus flower. He has a rounded face and a protuberance on his forehead. He wears a robe that covers his left shoulder. His hands are raised in front of him. Two standing figures flank the central figure. They stand on lotus flowers, wear robes, and have their hands raised. Their faces are simple. Two smaller figures are below the central figure. A tree with rounded leaves is behind the central figure. The plaque is light brown with darker brown areas. The background is gray, getting darker towards the top.