Same origin policies are there for a reason, so you'll run into a lot of headaches.
Manually you can have this in your curl.php to your server to accept cross domain requests:
To allow specific Domains:
header("Access-Control-Allow-Origin: http://coinshield.io");
To allow any Domain:
header("Access-Control-Allow-Origin: *");
You can also add this to your .htaccess file on the server hosting curl.php:
For any Domain:
<ifModule mod_headers.c>
Header set Access-Control-Allow-Origin: *
</ifModule>
Or for specific domains:
<ifModule mod_headers.c>
Header set Access-Control-Allow-Origin: coinshield.io
</ifModule>
And then test.php from coinshield.io:
http://coinshield.io/test.php<html>
<head>
<title>Michael</title>
<script type="text/javascript" src="http://videlicet.io/ticker.js"></script>
</head>
<body>
<div id="status"></div>
<div id="price"></div>
</body>
</html>
User would be able to include your javascript file to view on their site.
Last choice is use an iframe:
http://coinshield.io/iframe.html<iframe src="http://videlicet.io/test.php"></iframe>
This will maintain your security with same origin policies.
Regards,Viz.edit: added a couple more options