Use an array

<?php
$array = array('+23+67', '+75+789 ', '+76+297', '+256+91');
$cmd = " \( -size 475x873 xc:black \) ".
" \( cone.png -resize 30x30 \)  ".
" \( -clone -colorize 40% \)  ".
" \( -clone -colorize 20% \)  ".
" \( -clone -colorize 90% \)  ";
foreach ($array as $value) { 
$cmd .= " \( -clone -repage ".$value." \) ";
}
$cmd .= " -delete 1-4 -compose screen -layers flatten ";
exec("convert $cmd output.png");
?>