Just search: Passport photos (your city).
Make sure they understand that the PR Card specs are:
50 mm wide X 70 mm high (2 inches wide x 2- 3/4 inches long) and sized so the height of the face measures between 31 mm (1- 1/4 inches) and 36 mm (1- 7/16 inches) from chin to crown of head (natural top of head). Clear, sharp and in focus
Whereas the U.S. Passport photo specs are:
The correct size of a passport photo is: 2 x 2 inches (51 x 51 mm) Head must be between 1 -1 3/8 inches (25 – 35 mm) from the bottom of the chin to the top of the head.
Subtle differences, but they should be able to give you what you need.