One way to do this would be to use: context.getSite().getDirectory()/getName().You can also get the site name using the tokens -- but you probably wont be able to evaluate that in XSL as the tokens are resolved during the transformation.Also check the XML coming out of your component -- there maybe some info in the "headers" section.
referer = http://snv49003.uk.fid-intl.com/iw-cc/Site/Component/Preview.do?method=xmlFrame&ID=1215004666558&vpath=//snv49003/iwadmin/main/livesite/component/WORKAREA/Installed+Components//Content/Expert+Opinion/Expert+Opinion+-+List.component&siteVpath=//snv49003/default/main//Marketing/WORKAREA/Content/sites/site1