Oh, that's a shame - I think it may be because of licence fee issues: every household in Britain pays a compulsory licence fee to fund the BBC - it's something like £150 a year! - so it may be that BBC online isn't available oveseas because of that (??). However, the head is called 'Apollon Terroriste" http://images.google.com/imgres?imgurl=http://farm2.static.flickr.com/1149/1310841507_d7c74d4843.jpg%3Fv%3D0&imgrefurl=http://flickr.com/photos/yellowbookltd/1310841507/&start=1&h=334&w=500&sz=179&tbnid=EKvirJ6a_VqQ1M:&tbnh=87&tbnw=130&hl=en&prev=/images%3Fq%3Dapollon%2Bterroriste%26um%3D1%26hl%3Den%26safe%3Doff%26client%3Dsafari%26rls%3Den-us%26sa%3DN&um=1 - I hope that link works, but if not you can Google image search and there are a lot of online pages on Ian Hamilton Finlay.
Amazingly, the TV article opened with the presenter flying over a field where a speech of Saint-Just's is carved on giant slabs of rock, then the camera zoomed in on another carved quotation, the gold head, and other sculptures including what looked like a bust of Robespierre on a windowledge - and the presenter just said the artist was "inspired by the classical world"!