This symbol is obsolete. The US Government, its sole customer, uses it in only a few legacy contexts, and avoids it where possible. Replace "XX¢" with "$0.XX", "XX cents", an account of the coins themselves (e.g., two nickels
), or just "XX" (as on most first-class stamps).
If you want to be retro and hip, please remember that while $ always comes before the amount, ¢ always comes after.