I *thought* that details like this were available from Porsches custom service, where the rich and famous can request pretty much anything they liked.
I know on the 996 generation, gauge face colours were available....in fact, what you and I call white gauges are actually called silver faced, albeit very light silver....I still swear they're white, bloody marketing folk
There's a guy here in the UK that was approached many years ago by Porsche GB to do custom faces directly for them, for their exclusive clientele....really nice guy, he's repaired one of my flaking gauges (stock black, as it happens). His work is top-drawer and very reasonably priced.
He's a custom-car, hot rod guy, that kind of stumbled into doing this screen printing work for Porsche, and hasn't looked back....so....if you found the perfect car, but you didn't like the gauges, fear not, he can sort it out for you...964, 993, 996, Boxster, 997...he does them all, and for folks worldwide I believe.
If you get any of the UK Porsche mags, you may well have seen his adverts in 911 & Porsche World, etc. His name is Julian Reap, Reap Automotive Design (RAD), +44 208 863 2305.
A real nice guy, complete petrol head, and very helpful; I dropped-off my gauge with him on the way to a meeting one day last year, and he bent over backwards to get it finished in time for me to collect it 3hrs later on my way home. Now that's service for you!
No affiliation, just a very happy customer.
Hope that helps
Spencer.