I have done this sort of work for people in the past, and the results are a mixed bag. That is why I don't do it any more.

If you take a look at the "celebrity" morphs here in the marketplace, you will see that it is possible to get about 90% of the way to a real likeness. Most of the failure to go the last mile is not in the morphs, but in the textures. Short of doing a texture build from studio lit nude photos, you have to settle for a texture that is "close enough" to the person you are attempting to model.

I'm not saying you won't find someone who can do it for you... There are a great many very tallented Poser artists here in the forum. I'm just telling you to be ready to pay handsomely for the huge investment in time they will have to make, and accept the 90% results as a success.

$.02