Easy job. all you need is obviously the lights, grill and Front panel that the lights mount too. The panel is only bolted on and you could probably get one from a scrap yard for about 5 quid. Takes about 30-60mins to do the whole job.
Not quite sure why you want to do this though? If your trying to imitate a Rallye, The only similarity is that the lights are Both Square. The two are totally different, but who i am to dictate personal taste!