All Sitefinity versions are now available for download in your account.
In order to download the desired version, please go to your account at www.sitefinity.com
and then go to Products and Subscriptions -> Sitefinity
and click the Download
button. Then please click on the Older versions link
of the Sitefinity 6.3
version and you will see the list of the available versions for download.
Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.