no, not a krieghoff, all krieghoffs were marked on the toggle that I know of and krieghoff only made around 13,000 lugers, so your serial number is way to high.
Strawing was originally on most lugers; the trigger, safety lever and other small parts were not blued. They will appear lighter, almost like it has
worn bluing, but is in fact, made orginally that way.
See how the trigger and other small parts are not blued looking
Ed