No reference for a savillion rifle. If you mean civilian, same as for a military rifle- it will depend on the caliber and barrel. Military rifles in the US are made by civilian companies.
25-100 USD, 12 gauge is a shotgun, not a rifle.
8
The 7mm designation is a reference to the bore size, or diameter. In decimal size it means this rifle has a barrel groove diameter of .284 inch.
12 gauge
You must mean the Model 97. Model 94 is a rifle?
Entirely dependent on what the maker reference is.
Never heard of a 12 gauge rifle.
You can have one made.
No. Caliber is the term
Sorry- that is a serial number, and conveys no information. If the barrel is not marked, you need to take it to a gunsmith who will measure the chamber- not only for gauge, but for the correct shell length. Just because an unfired shell fits does not mean it is the correct shell. And it is not a rifle, but a shotgun.
No such weapon in any reference I have