Vaulting 1-3 Romanic 750cm spaced simple Low-poly 3D model is available on CGTrader for $14. Original author: ar3ding. Specs: 747 polys, 786 verts.
OBJ (OBJ, filesize: 10.7 MB), MAX (Autodesk 3ds Max, filesize: 5.35 MB), OTHER (Other, filesize: 5.78 MB), BLEND (Blender, filesize: 5.86 MB)