Not that rare, but very lovely. As for value, I reckon they sell for about 30% more than an SMLE in similar condition. Thus in the UKicon, would sell for about £600 - £800. If it has a good shooting bore, it's worth more - but it is most unusual to find a really good bore on a long Lee. They are a pleasure to shoot - if the bore is good - but the sights are a bit crude.