How common are the '97 F250's in gold with white?

 

I saw one today.
I get a lot of windshield time with my job, and can't say I've paid any attention to colors of trucks, but since I read your post last night, I've paid more attention.
Today I saw one. A 4 door 4x4 longbed.

 

You mean like mine? They are out there. I think they're about as common as any colour scheme. Ford had a lot of colour options back in the days of the OBS and prior. Its rare to see too many that are identical (except for the XL trucks that were sold as fleet trucks which are usually white or grey, tend to see lots of those)