Surface finish should be easy enough to clean up afterwards by hand if a reasonably close copy of the basic structure can be 3D printed. Biggest issue is reproducing the wood grain-ish pattern. I have heard it described as "Featherwood" but to be honest, I don't think it is a read life wood grain. I have a couple of guitar hand builder friends, and they don't think this is actually a copy of any natural wood. I did look up featherwood, and it is supposed to be a tree that grows in some parts of Australia. I think, if there is a way to get a stable structural support, that it would be easiest to just veneer a dark grained wood, and then urethane coat the venner. More than likely would last a lot longer than the original parts, and depending on how stable the strucral part is, or if the structural part can be re-inforced around the door lock plunger, it will not crack like the factory parts do. If one wanted to get really ambitious, you could veneer the dash panel as well, and get everything to match up, and also, the same colour. I don't know about everybody else's cars, but mine have a variety of browns to pinks, depending on who much sunlight they have been exposed to over the years.
Kostas