vintage f300 seamaster need help on crown and caseback

[sotongster]

Bought this today; looks quite pretty for it's age. But as I sit at my desk; I just realised three things.

1. the caseback's plain. It doesn't have the seamaster logo. Is it normal? What is the worst thing here? That I got a new caseback that isn't omega's original seamaster?
2. the crown doesn't seem to have the omega logo. Did i get a fake crown? Does anybody know the part number that I should be looking for?
3. The hands look like original, but also realised they're black in the middle where the lume is supposed to be; as though they're the same color as the second hands. Should I be concerned about lume removal and the hands being painted in black?

New to vintage watches and this guy humms so I think the movement, case, hands and dial should be legit. Just wondering if I should worry about the above points...

 

[X350 XJR]

I believe this is a reference 198.001.

Many of this reference had plain backs.

Crown is a replacement.

Hands and dial should have lume.

 

[sotongster]

X350 XJR

I believe this is a reference 198.001.

Many of this reference had plain backs.

Crown is a replacement.

Hands and dial should have lume.

should i be concerned about anything since the hands look like they were reworked? paid about 360$ for this watch. and the dial's lume (if any) looks too small to be seen.

 

[JJF]

I also just picked one up - looking to find an original crown or at least something Omega/right size as the one I have is clearly not a fit

The last picture (on a strap) isn't my watch but it's what I think the crown should look like

 

[JJF]

X350 XJR

I believe this is a reference 198.001.

Many of this reference had plain backs.

Crown is a replacement.

Hands and dial should have lume.

Do you have any idea what the part is or where to get an Omega crown that would fit?