I'm not aware of a kit, but I know that the 1984/85 kit will not fit the 1986 carbs.
You don't need a kit. Just bump the main jet up two sizes, and the slow jets one or two sizes. (depending on where you like your pilot screws set)
If it's a matter of needing the needle, you can just re-order the stock needle from a Honda shop and use bigger jets to make the mixture richer.
2010 Honda NT700V
1986 Shadow 700
1986 Honda Trail 110 (Postie Bike)