Newspaper, gun show, gun shop, Shotgun News, etc..
yes----
They are used for hunting, sport shooting, and used by the military.
The 7.65mm Mauser rifle is MORE than adequate for deer hunting- IF a soft point hunting cartridge is used. Full metal jacket military ammo should not be used for hunting.
Many hunting stores sell both new and used equipment, so it is likely that one would be able to find used Nikon rifle scopes there. As well, many are available online at stores such as Amazon and eBay.
Long range hunting, the lower end of big game hunting.
If a rifle is permitted for hunting, semi autos can be used in MOST states. Pennsylvania does not permit them for big game hunting. You would need to check the hunting regulations for YOUR state.
Hunting, shooting, self-defense, military
Game of all size and shape is hunted, and the calibre varies in accordance with what it is you're hunting. If you're hunting elk, you're not going to use the same calibre you would hunt squirrel with, and vice versa. A hunting rifle is simply a rifle which is used for hunting - that in itself doesn't determine what's being hunted, and it would be impossible to determine an average calibre, given that not every hunting rifle was a purpose built rifle - some hunters, for example, used decommissioned military rifles such as the SKS.
ebay or Gunshops
Deer taken by gun rifle/slug and by bow.
Hunting, shooting, collecting.
it depends on what your hunting