The LEGO Group has already created gold C-3PO minifigures
LEGO Set fig-000571 C-3PO, Chrome Gold (30th Anniversary) (2007 Gear) | Rebrickable - Build with LEGO
Custom Lego Gold & Chrome C3PO Minifigure
Just purchased with great luck these two US and European variations of Lego Chrome Gold C-3PO minifigure in like new condition from private collection. : r/lego
LEGO 4521221: Gold Chrome Plated C-3PO | Brickset: LEGO set guide and database