It is true that the 1950 and 1951 mintages were supplied for the West Indies. However, once news of the 1950 low mintage got out a year later, collectors had as many 1951s as possible shipped back again, which means they were always easier to find in BU than the 1950. So many were shipped back, in fact, that even in the 1960s they were sold in bulk ("You want 10? 100? No problem.."), and snapped up as an 'investment'. It was very hard to find one in your change though, but 1953s were possible despite only existing originally within the plastic sets. You know, this is where the eye appeal lends itself to judging a coin. While the 1953's are plastic set issues only, they are ugly as sin and render the coin valueless (to me anyway) because of the weak striking, flat design and horribly uncomfortable positioning of Britannia. As people have mentioned before, this is very much subjective so what someone might class as rare, doesn't necessarily mean 'sought after' or 'hard to obtain'. I propose the following - a few different rarity scales (i.e one for mintage numbers, one for eye appeal, one for market appearance etc.) then once the coin has been indentified on these, an average or combined score should be plotted against some sort of 'Master rarity scale' to judge a coins overall rarity. I get it though...easier said than done..