https://en.numista.com/catalogue/pieces405.html
Apart from the crease (on the site below called strap) it also says there are two versions -
whether near or far leaf on the crease coins. Just as near or far without crease. So four versions of 1953 and no versions of 1954 which makes five versions of KM# 50 altogether!
http://www.ngccoin.com/poplookup/WorldCoinPrices.aspx?category=33&worldcoinid=253&FromSearch=true
As for grade, I would say pretty low due to the deep gouges on the obverse. On the above for say VF20 grade the price of $0.40 is the same with or without strap. Then with strap far leaf is $300 and best is without strap near leaf $700 price.
Maybe someone else knows how to tell leaf type.