if it has the original barrel in it you can get the month and year of manufacture from the two letter code on the left side of the barrel just ahead of the receiver.
The 700 was introduced in 1962....year code J.....so therefore
1963 K
1964 L
1965 M
1966 N
1967 P
1968 R
1969 S
1970 T
1971 U
1972 W
1973 X
1974 Y
1975 Z
(then they used I,O,Q and V, presumably to start with A in 1980)
1976 I
1977 O
1978 Q
1979 V
Then in 1980 they started over with A.........you can get it from here....
The months are as follows
Jan B
Feb L
Mar A
Apr C
May K
Jun P
Jul O
Aug W
Sep D
Oct E
Nov R
Dec X