By coincidence I saw a red 7.5 today (a bit scruffy tbh) with Parkers that had been painted or powder coated a uniform mid-grey. No black inserts. Just overall grey.
Memo to self : NEVER do this!!!
IMHO OEM diamond cut alloys with wide spokes such as mk7 GTI’s Austins and mk7.5 GTI’s Parkers don’t look great when refurbished in a single colour; the wide spokes make them look very heavy. Just my opinion though, and no offence intended to anyone who’s had their Austin or Parker alloys powder coated in a single colour.
I may be wrong, but I seem to remember the OEM standard alloys on the mk7 GTI in Germany was a silver powder coated version of the Austins. I think may have been 17” rather than 18” and were possibly called Brooklyn rather than Austin, and they were also sold in some markets as winter wheels.