A couple of things regarding your Luger.
1st off ... congratulations ... like jimmiej says 'they are addictive' so make room for more.
2nd ... the trigger plate is definitively an aftermarket replacement IMO.
I think the original was probably damaged around the time the 'amateur' tried to force the take down lever down and 'broke' the round end from it ... insult to injury he then rounded the end to make it appear 'normal' lol.
Also your left grip has the dreaded million dollar chip which doesn't really affect the value because this is an obvious 'shooter' grade gun BUT it is still nonetheless a Luger and therefore deserving of a loving home and owner.
Have fun Garandsrus ... that's the main thing