Nice choice in the rifle.
The European models show, or have shown, sight & BOSS together. So, that was a factory option if you're a Euro~!
Physically, then, the job could be done by a good gunsmith, and you could have both.
I have a 7mm Rem.Mag. version of the Safari MkII with the BOSS, or "B.O.S.S." to be absolutely correct in the abbreviation.
It is my nicest rifle, for sure. Shoots really well, and feels good when doing it.
I would not try to retrofit a BOSS on the rifle you have, though. It would be cost prohibitive and overall end up being a major PITA, in my opinion...
It would be easier to add sights to a rifle that already had the BOSS on it.
BTW, the BOSS bbl. is about 2" SHORTER than the ones with sights on it, if I'm not mistaken.
You're .308 is proabably better the way it is than if you'd bought the BOSS model. It could theoretically be better with the addition of the BOSS, but it's a gamble.
Also, you end up fiddling around with about as much ammo either way.
The real advantage of the BOSS is MAKING the rifle like what you want to shoot.
I hope that wasn't too much of a ramble.
Good Luck!