A blend of a basic knife, should be in correct scale 21cm long throwing knife. (8,2 inches) untextured use flat shading for a sharp result. 430 verts - 946 edges - 946 tris
An image plane would cover the UV unwrapping
Well yes I do think so, but since it probably won't need to be deformed, and looks best with a flat shader I think it will work out fine. UV mapping would probably not be necessary. But if you see a problem with it I should probably fix it.
Sorry about the image resolution. If you're wondering about material and colour of the actual knife: it's pretty much metalic black with the exception of the cutting edge of the blade.