The NHS one goes to 6'7", so a bit of extrapolation shouldn't be difficult:
http://www.nhs.uk/livewell/loseweight/pages/height-weight-chart.aspx
This Huffington Post thread however rejects the 'standard' BMI chart, particularly referring to how it gets it wrong for a person who is 6'8" tall. There are links both to the standard chart and to one which the author proposes uses a better formula (with both including a height of 6'8"):
http://www.huffingtonpost.com/david-belk/body-mass-index_b_7693450.html