Looking at other pictures i have found online, i cant see a gap for the bezel, telling me if it were replaceable or not.Basically , under magnification, if you see a tiny gap between the bezel ring itself and the case, it should be replaceable.
If none can be seen, the case will have to be replaced, Or the bezel area can be refinished. I think it can be refinished, so long as it is made of real steel.
Yep , as Ganson said, to refinish it, it may removed quite a bit of material. But if it is done with care, it will look even, and like it was supposed to be that way. That ding doesnt look more than a 1/5th of a mm in depth at very worst. And we may say removing alot of material, but in essence , its a tiny amount really.
I have filed and sanded out stainless steel cases with dings worse than that.
The only worry i would have , is that it might make the markings on the bezel a little more shallow .I cant really tell from the photo, but the numbers look pretty deep, so it probably could be done. The watch would have to be opened, the movement taken out, and the crystal with its gasket , removed before work could be done on it. After the ding is filed and sanded out, the texture will have to be put on again. And likely , the bezel indices would have to be repainted.
All of this could be done by a careful watch maker. It can be tough work, but is doable.
Rod