This is a paid asset, but now you can download Tribal camp Free.
Detail this asset from Unity Store: Original Link
Tribal camp v1.0
Here you can find a lot of different elements of tribal architecture and few pregathered elements.
Package keeps full PBR sets of 4096×4096 textures for each material.
Triangle count for elements between 32 tris for smaller element and 2370 tris for bigest.