Please check your pocket change. ALL US coins have the motto E Pluribus Unum on them so that's not anything that ID's a specific coin. In any case, huge quantities of cents were struck in 1957. Please see the Related Question for more information.
If it comes out of pocket change it's worth a penny. In bulk copper wheat cents will get 2-3 cents each due to the value of the copper. If it is in mint condition and absolutely unworn and untouched then it may fetch a couple dollars.
The 1957 Roosevelt dime is 90% silver. Its value would be determined by condition, date, mint mark and collector demand as a numismatic item. Silver content may be of more value than its numismatic value.
It was made in 1957. You need to let a dealer look at it to determine the value since that depends on the exact condition. This rifle was manufactured in 1957. The value depends considerably on condition. Have it professionaly appraised.