push button timer

would like to build a push button timer. push the button the timer is set for 17 min then alarm goes off. also the timer must be able to add 1-2 minutes and subtract 1-2 minutes if desired.
push button again to turn off alarm. (nothing more than the simplist alarm clock that turns on when pushed and off when pushed ) please help

Do you want to do it with one chip?

whatever is cheapest and can vary up 1-2 min or down 1-2 minutes

An 8 pin chip is 38 cents.