Calais fronts, as in eyelids, nose cone, grill and motors? They're still getting around for sale for around 500 on here. Depending on the condition and with badges or not it'd either go more or less. 400 would be a quick sale.
Having said that, people aren't going to stop wanting them and they should get rarer. So it depends how patient you are.
Bax is right on the button I reckon...
You could probably do a search on the FS section for 'calais front' and read peoples old FS threads... that and an ebay completed listings search...