All the pictures I have seen of the S/T version have actually had something on there about it. Have a look at the picture I've attached.
Now I not sure how old this picture is, and whether it has changed, but this is generally what I have seen, and I've not seen the word Education appear on the packaging for the S/T version.
As for the shop telling you it's the correct version, itd always pays to do your own research....There have been several reported cases on this forum, where a well know shop has sold the wrong versions of Reason to their customers - Incorrect upgrade versions seem to be a popular "mis-sell".
The fact that you only have an Upgrade ID, also seems to suggest that you have been sold an upgrade version instead of the base licence....