The term Sede Vacante means Vacant Seat and refers to the period of time between Popes. The dove on Sede Vacante coins represents the Holy Spirit (Sancte Spiritus). Lire denomination silver coins were minted by Vatican City during Sede Vacante of 1939, 1958, 1963, and 1978. In 2005 they switched to euros. You have to know how to read Roman numerals to figure out the date.
Here are some typical catalog values for fully uncirculated coins. Circulated specimens will be worth less, but never less than the value of silver they contain. Look up silver values at kitco.com.
1939 5 LIRE: 0.1342 troy ounces silver, $50 fully uncirculated
1939 10 LIRE: 0.2684 troy ounces silver, $50 fully uncirculated
1958 500 LIRE: 0.2953 troy ounces silver, $70 fully uncirculated
1963 500 LIRE: 0.2953 troy ounces silver, $20 fully uncirculated
1978 500 LIRE: 0.2953 troy ounces silver, $20 fully uncirculated