This is a great 3D scan of an ancient Roman marble plinth I found here: http://www.123dapp.com/catch/Roman-marble-plinth/2369229
It model has great quality, I only had to make a flat base by plane cutting and scaling the model up by using MeshMixer (http://www.meshmixer.com)
The author marked this model as their own original creation. Imported from Thingiverse.