Found it. Anyone with a similar problem can add this code to their site plugin or theme functions.php
function convert_numbers_to_arabic( $string ) {
$arabic_numbers = array('۰', '۱', '۲', '۳', '٤', '۵', '٦', '۷', '۸', '۹', '.');
$english_numbers = array('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '.');
return str_replace($english_numbers, $arabic_numbers, $string);
}
add_filter( 'get_the_time', 'wpse_convert_arabic_time' );
add_filter( 'get_the_date', 'wpse_convert_arabic_time' );
function wpse_convert_arabic_time( $the_time ) {
if ( get_bloginfo( 'language' ) == 'ar' ) {
$the_time = convert_numbers_to_arabic( $the_time );
}
return $the_time;
}