DJ 1601 Originality and Case Condition?

[SigmaMade]

Hi all,

I recently acquired a vintage datejust on the bay and it was one of my first watch purchases after some research. Not surprisingly I've passed through this forum numerous times during my hunt. The serial number on the datejust seems to suggest that it is a 1973 model (3XXXXXX). It has a sigma dial with open 6 and 9s. I was wondering if forum members can assist with their expertise in the following matters:

1) Are the parts original to the watch? Is it a redial?
2) Has the watch case been polished?

From what I can tell it is authentic, and parts look original to me but I believe the crystal may be a service replacement. Lume plots appear to match the hands and dial condition appears to be fairly consistent with the case (both in decent condition). The case seems polished but the satin brushing on the lugs still appear to be there. Fluted bezel appears fairly sharp and not too rounded. Also, the case doesn't appear as sharp. All these factors leads me to believe that polishing is slight.

Any help would be appreciated. As this is my first time putting my money where my mouth is so to speak so I'm just curious as to how I did.

Images: https://imgur.com/a/SG72rIh