I'd say it's two to three days from Kingston to Westport on Champlain. Boogey up to the Fed, expect some delay and then about 10 mph which is the limit on the canal until you pass lock 12. Once North of the last lock watch the channel in the wide open spaces. It may be difficult to pick out the markers since they are spread out.
It's a great ride, settle back and enjoy it. It's been since 1999 since we did that trip so I can say much more.