This is a piece from the friege that decorated the mausoleum of Halicarnassus( Μαυσωλείο της Αλικαρνασσού). It is found at the site of the structure in Bodrum, Turkey. Most of the temple has been transported to other places. A significant number of pieces can be found in the british museum. Scans of other parts of the friege allready exist:
https://sketchfab.com/models/56a3210a2d8f4a55a5b9ae69f12f05c0
https://sketchfab.com/models/71112f81a608421582b63cc18a9268d0
The width of the model is around 1m
If you have more information about the piece write a comment and I will add it here.
The model was made on the 8/10/2017