It is your call. It all depends on what you are after.
If you are looking for a collector rifle, then yes you would have to hunt down all the correct parts, etc.
If you want a rifle to go shooting and have fun with, I personally would not change a thing.
You have from the looks of it a very nice SC '03 that someone has changed/upgraded to their taste by changing the stock and trigger guard.

Are there any cartouches or any other markings on the stock? If there are could you take a closeup picture and post it.

Why were you taking it around to get it appraised? Thinking of selling?

Where are you located?

D.