Our Kirby office (in early 1980s-early 1990s when i worked there) had a gold Kirby of every model since the 516. The office was owned by the same family all those years,,and as far as i know, still is.
Id have to say the Classic 1CR and Classic Omega in gold were the coolest looking,,and especially the DS50 or any of the "Sorocco" colored 500 series machine,,the gold was really cool looking on those blended with the tan. The Kirby Tradition in gold is beautiful too. I dont know for sure if ALL of his gold plated machines were sales awards but i know some were,,i kinda think there were a few of them that he just had done that way on his own. Those gold plated machines really did look cool all lined up together. Wish i woulda/coulda had a pic of that.
I know i saw a gold plated G5 on E-bay once a few years ago,,but the gold plating was starting to peel.