Or for much less there's plating pens. Still paint with conductive paint but then use the small solution pen to plate it. I've been planning on implementing this for months with my business, just waiting on my Form 1+ to be shipped... Hilco (optical supplier) has been asking this for years to replate glasses:

http://bt.e-ditionsbyfry.com/magazine/index.php?i=117349&m=&l=&p=185&pre=&ver=swf#{"page ":185,"issue_id":117349}