I do wish there was a site with differant handle materials just for show and tell. I may add something like that to mine if I ever have time.
FWIW, ask him. For the field I'd go with stabilized wood for the natural or mycarta. Probably bead blasted mycarta for grip, but it realy depends on the knife shape and what you intend to do with it. I love desert ironwood, but unless the owner is willing to take real good care of it I wouldn't suggest it. If it's full tange you might find it hard to get stag or bone large enough to fit your design. I do like giraffe bone, but I think it's fallen out of favor collector wise, might be wrong about that.
One posibility I want to try is TruIvory, it's a synthetic ivory substitute used primarily for grips and looks and works just like the real thing. I've got a set of scales I haven't had a chance to work yet, but there very hard unlike the cast poly resine and won't pick of scratches as easy.
Mokume might be a little over the top for a user, but if the design works out for you you might want to make a "presentation" grade version.
Can you post a pic of the design? Oh, and forgive me, but is 10v carbon or stainless? I cant remember. My general rule for my knives, though there are many exceptions, is that carbon steel generaly gets natural materials and stainless gets synthetics. Mainly my resoning on that is the blade and handle will age together. Ie. I won't wind up with a blackened and stained blade and pristene handle, and I won't have a bright and shiny blade with a darkened and well stained handle.