I suspect that there is no recycle bin. Would it be possible to copy/paste a folder with files from a test-environment to the live-environment? 

Here is how you can get the files back: 

Step 1. From the web.config, check the physicalPath of the Global Files: 

<virtualPath customFileSummary="~/FileSummary.config">
        <providers>
          <clear />
          <add showInFileManager="true" virtualName="Page Files" virtualPath="~/PageFiles/" bypassAccessCheck="false" name="SitePageFiles" type="EPiServer.Web.Hosting.VirtualPathVersioningProvider,EPiServer" indexingServiceCatalog="Web" physicalPath="\\servername\site_content_livebackup\cms_content_live\pageFiles" />
          <add showInFileManager="true" virtualName="Global Files" virtualPath="~/Global/" bypassAccessCheck="false" name="SiteGlobalFiles" type="EPiServer.Web.Hosting.VirtualPathVersioningProvider,EPiServer" indexingServiceCatalog="Web" physicalPath="\\servername\site_content_livebackup\cms_content_live\global" />
        </providers>
        <filters />
      </virtualPath>    

This physicalPath contains a lot of folder, with a lot of subfolders, containing files with guid as names. 

Step 2. Get the connection between the filename from the File Manager and the guid.jpg from the physicalPath. 

Go to the db, and execute this query: 

SELECT pkID, fkSchemaId, Name, ItemData 
FROM tblItem
WHERE (Name = 'accidentilydeletedimage.jpg')

This gives you a Guid. Copy/paste this guid in the RelationListFrom-SP: 

exec RelationListFrom @FromId=N'pkID',@SchemaId=0 

This gives you another Guid. The accidentilydeletedimage.jpg has this guid in the physicalPath. 

See also http://world.episerver.com/Blogs/Petter-Klang/Dates/2011/4/Finding-your-Versioned-files-on-disk/