With the frame pre 1913 without stock lug, the safety would be more 'correct' if not stamped 72. Looks like the previous owner desided to put 72 on this part himself.
This is a usefull thread regarding the front sight;
http://forum.lugerforum.com/showthre...ht=front+sight
I don't think the Luger is that bad.. it has had a long life and would make a great 'shooter'.