Find a gunsmith and ask for help.
Yes
100-1000 usd
If you don't have an owner's manual, go to a gunsmith and ask for help.
Doubtful. The .308 Norma Mag was a fairly short lived cartridge, and competed with Weatherby's own line of magnum rifle calibers.
50-1000 USD depending on specifics
A Browning safari grade bolt action rifle in the excellent condition you describe will bring between 1,375-1,500 dollars for a gun with between 90%-95% overall condition,and a good bore. There were not many of these rifles chambered for the .308 Norma Magnum caliber.
Get it to a gunsmith now.
Norma makes ammunition, not rifles. Accuracy will depend on WHICH rifle is firing the .308 Norma Magnum cartridge. Many are Schultz and Larsen products, others are hand built conversions. Accuracy will depend on whether it is a target rifle or a lighter sporter grade rifle. The round has pretty much been bypassed by the .300 Winchester Magnum cartridge.
If you google "308 Norma ammuntion" you will have a start
Try e-gunparts.com, gun shows, gun shops, want ads. for sale ads.
The 308 Norma Mag is beyond a hunting rifle. It is more of an AMW. (Anti-Material-Weapon) or a very long range sniper rifle. If the rifle is in good shape and still has the standard wood stock and medium barrel, I would say it is worth $1,000.00 American dollars.
Good luck in your search for a .308 Norma Magnum. There were few gun makers that used this caliber. You might contact the Danish gunmaker Schultz & Larsen through their website, and see if they are still making them (they developed it) and who is a distributor in your home. Ammunition will also be very hard to find, and extremely pricey.