I believe this brand is owned by Diageo - if so we will be able to have your bottles dated (thanks for the photo). As for a value, you'll need to try McTears.com or Bonhams.com. And, for more information on President Scotch - see below:
President Scotch whisky was first registered in Brazil in 1944, then in Venezuela in 1955; subsequent trademarks for other markets followed in the late 1950s and 1960s, including Hong Kong and Japan. The word 'President' had been trademarked in the United Kingdom in 1906 (not for whisky) but it wasn't assigned to Macdonald Greenlees until 1965. President apparently replaced another Greenlees brand, Supreme Liqueur, which was withdrawn after the Second World War when a general prohibition was imposed on the use of the word 'liqueur' for whiskies following protests from liqueur producers.
President Scotch whisky is sold largely in Central and South America, but you can also find for sale online.