YIKES! These are bad bad redials! Why are they on your radar?
The 5XX movements are 28mm wide, the watches that use them come in many sizes, unsurprisingly all greater in diameter than 28mm but not limited to particular sizes. The movement can be (much) smaller in dia than the dial. The 321 or 861 used in the 42mm wide Speedmaster is only 27mm wide...
I also think the dial you’ve found is original.
The arrow-head markers are slightly wider than the ones on your dial and don’t contain any lume.
Note the seconds hand is missing!
Be sure to check the furniture on the donor dial is the same colour and matches the medallion of your case back.
i.e. you don’t want to be mixing rose gold and yellow gold.
Also most importantly make sure it’s the correct dial for your case/movement as per @padders comments above.