Hmm, to me this looks like a standard Silix case. The Silix is not gen spec with a "sandwich design" (ie threaded midcase ring) - the bezel is press fitted to the mid case and a 6497 fits without any extra rings. Have you tried just fitting your parts? Crown looks custom though and could need some work (retapping hole, securing crown tube of right size etc) - a way around this is just to find a standard silix crown. Depends on how much mod work you wish to learn and do.
Most probably not. The WL case is a 3 piece design 3646 style, where bezel and caseback screws onto the movement ring. On the 6154, it's onto midcase itself. But... I've never tested, so you never know
Send the 16030 case to rolojack, he does wonders transforming 160xx cases to 1016 spec. Re the Yuki bracelet - my endlinks fit great to my 1601 case. However, it is an odd bracelet with those fixed endlinks (you'll also have to enlarge to fit fat spring bars).