Seamaster 2846-5SC 2848 thoughts? Lots of macro pics

My jeweler picked this up recently. To me it looks all original (less the crown). Model 2846-5SC, Caliber 490, serial 15.2 million. My research puts this circa 1956.

Dial looks all original to me; Geiger counter reads radium. Did this likely start as off-white/champagne and patina to its current color, or did it start as a brown tone?

Hands look to match perfectly, and in good shape.

Case looks unpolished. What was the original finish for this case? All brushed…or all polished…or?

Crystal is signed but pretty scratched up. Crown is wrong, I believe- since not signed. Can anyone tell me which crown I’m looking for?

490 movement running and keeping good time thus far, but you cannot wind it (however, time setting feels smooth an unencumbered). Definitely needs a service, lots of grime on/in this old watch.

And what is the meaning of the 2848 engraving in caseback; were they transitioning to that new model?

The 18m straight-end bracelet is from Flex-Net, and it very vintage cool. And it feels great on the wrist, light, yet secure.

Hope you enjoy the pics and I look forward to any insight.

To add regarding case condition-

I think I’m going to fix this up and give it to a buddy. I don’t have any experience with reconditioning of vintage omega dress watches. It would be a rare case where I touch a Rolex or UG case, for example. However, if I want to gift this to a professional who will wear it in the office, can this case withstand a sympathetic return to original finish (even if it means losing a little metal)? Or leave well enough alone, even if aesthetic is important to me?

Nice original watch. Polishing the case would be a mistake just hand buff with cleaning cloth if you must.
Polywatch the crystal will also help
Don’t open it yourself radium not to be messed with by amateurs
Not everyone wants to wear a radium watch may not be best choice for a gift.
Dial aged to this color.
2846-2848 is double reference 2846 is central seconds and 2848 sub seconds like yours.

More info here

Something like this for the crown thick scalloped type

Point taken about wearing radium, so I asked him if he’d wear a radium watch.