Glass Size ??

Hi Everyone,
I have just purchased a 1973/74 Omega De Ville TV Dynamic.
The watch in my opinion is stunning, and very trendy!
The problem I have is that the glass has a very small chip off of the top left hand corner.
I have scoured the internet to find both the glass size dimensions and also where I could purchase a replacement, both without any joy.
Can anyone point me in the right direction.
The photo is of the actual watch I've purchased even though the photo is from the sellers ad.

Kind Regards
Shaun

Further to my original post, I have been on the official Omega site they have a very grained old picture of the exact 1973 TV Dynamic in Black.
However they do not have a user manual / spec sheet anymore for my model.
The model no is 166.0187

Thanks so much for the info.
Now to find a supplier!