The stocks are clearly original. Whether the medallions are silver or gold is debatable. They look like silver on my monitor, but enlarging the picture reveals a more "goldish" hue. Maybe someone should ask the lady with the nicely painted fingernails?
The nice fingernails belong to an eBay seller called "coltelitegirl " and she has lots of grips/stocks for sale.......not all are colt. coltelitegirl | eBay
Many look like Altamont made stocks to me but I am a rookie at this ;^)