Yesterday G-Central posted an interesting article about custom full-metal DW-6900 here. I Googled it a bit and found out you can order these aftermarket metal band & bezel in Aliexpress, but it costs more than 100 euro and it's aftermarket stuff after all.
However, I crafted my own not-so-metal DW-6900 a couple years ago using genuine Casio parts. Here's some photos and a the secret formula:
DW-6900 case & module
DW-5000 D-8 JF band
Some white paint for the G button.
Hope ya like it. Anyway, I 100% agree with G-Central article that Casio should release a full metal DW-6900 someday soon. It's their second more iconic model and one of their best selling models of all time after all, isn't it?