Polikarpov I-15bis (Polygon mesh 3D model) is available on CGTrader for $10. Original author: fumio-yamazaki. Specs: 59634 polys.
OBJ (OBJ, filesize: 32.6 MB), 3DS (3D Studio, filesize: 41.4 MB), JPG (JPG, filesize: 106 MB), LWO (Lightwave, filesize: 32 MB), MAX (Autodesk 3ds Max, filesize: 32 MB), BLEND (Blender, filesize: 34.5 MB), GLTF (glTF, filesize: 24.6 MB)