I had a buddy that sent his OE Valk top clamp to a firearm engraver, and it looked pretty amazing when he got it back.
The aluminum will take a mirror shine, but then it becomes another issue like the gas cap for reflection in your eyes and the windshield.
Years ago, when I ordered my first Aeromach Honda pullback risers, I also ordered their
Reaper top clamp (which they say only works with their risers). I was worried about it hitting the taller interstate gas tank, but it clears just fine (with the taller risers). Also, pretty unique. I was not aware they were still making them (this says for Kawasaki, but may fit their Honda risers too). And yes it is also pretty bright.
http://www.phatperformanceparts.com/Aeromach_Reaper_Top_Clamp_for_Honda_p/am-3430c.htmhttp://www.aeromachmfg.com/Reaper_Top_Clamp_p/am-3560c-d.htm
Know nothing about this.
http://www.jpcycles.com/1998-honda-valkyrie-tourer-gl1500ct/handlebar-riser-top-clampsThe other thing that could be done would be to glue one or more bike pins to it, or a collector coin, or a badge, and it could easily be tapped for mounting such things as well.