Should I buy a Omega Speedmaster 105.012 with Modern Bezel

I'm currently looking at a 105.012 from a private seller, BUT it has a modern bezel on it.

Couple of questions here:

1. Any advice on how much it'd cost to replace that modern bezel with a period-correct bezel? How much should I expect to pay to acquire a bezel and the cost of labor to replace it?
2. How would I go about doing this? Would I find a bezel myself and take it to a restoration/repair shop? Or would a shop do both?
3. Is this worth doing at all? Wondering how much a discount I should ask because of this bezel.

Sorry, I don't have good pics, but to my eyes, the dial appears good (although not sure I like how the lume looks), the movement appears to be good, the case looks a bit polished (I'm not really seeing strong sharp lug lines).

Any thoughts appreciated!

Yes

I suggest you check out Omega forum member @Spacefruit's informative Speedmaster website.
The price chart also mentions the DON bezel.
https://speedmaster101.com/price-chart-2/

If I were to replace the bezel, I would get the bezel myself and take it to a good watchmaker's store to have it replaced.
Bezels are available for sale on ebay and in the 'Watch Parts and Accessories For Sale' section of the Omega forum.
https://omegaforums.net/threads/omega-speedmaster-don-bezel.123852/
https://omegaforums.net/threads/fs-do90-bezel-for-speedmaster-mint-reduced.118074/

It is your decision whether or not to replace the bezel.
Consult your budget as well.