1. The coloured DAL 35s are to be on sales in Japan on November 19:-
http://dc.watch.impress.co.jp/docs/news/20101029_403462.html
If you want to have a closer look on the appearance of those painted DAL 35s, view here:-
http://www.camera-pentax.jp/k-r/simulator.php#090411
2. (Charged) grip exchange service for a new colour for the K-r, K-x and K-m:-
http://dc.watch.impress.co.jp/docs/news/20101101_404029.html
(See the machine-translated English page for more details.)
As for the cost, replacing the grip of the K-r requires 5,250 Japanese Yens, whilst that for K-x and K-m is just 4,200 Yens. Time required for the job is three working days.
Related:-
How to Order a Custom Coloured K-x from Japan by Yourself?