The dial looks OK to me. There is a fine line between damage and patina and this example is right on the line, in my opinion.
According to
@mondodec's list of calibres the 504 is something of a rare movement. With that late a serial number it must have been one of the last produced. I have a cal. 561 with a similar number 1721xxxx in a 14393-1 case.
The crown looks wrong to me. The medallion shows more wear than mine too.
Now, mind these are two different models but I purchased my piece about 3 months ago for a bit over $800US.
View attachment 322478
View attachment 322479
The example you are looking at is a snap cap back and mine is a screwback.
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