If you're selecting a quiver based on typical slalom race / freerace sailing (as compared to say, GPS speed etc) then a good 3 slalom board quiver for your size / sail range will be :
1> iS86 (5.9 / 6.6)
2> iS101 ( 6.6 / 7.6)
3> iS122 (7.6 / 8.4)
3a> could be iS133 if you really wanted to increase low (slalom) wind range and/or margin for racing in "marginal" slalom conditions.
Cheers ~ Ian